New 100-400 lenses
p.16 #1New 100-400 lenses
MMP wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.
Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
Jun 04, 2026 at 02:23 AM
p.16 #2New 100-400 lenses
duncangr wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
Not knowing the specifics, the lens does contribute to autofocus performance in several ways.
1. Optical quality: aberrations such as longitudinal chromatic aberration can lead the autofocus to hesitate between focusing the different colors. Lenses well corrected for LoCA tend to focus with less hesitation and better reproducibility. The use of a TC can increase aberrations wide open (and leads to a smaller aperture) and thus lead to slightly reduced performance in autofocus.
2. Depth of field. A faster lens gives more light and the distribution of incoming light angle rays is such that the focus is better defined, at least if there are no aberrations. AF benefits from both. (In case of the 100-400/4.5 + 1.4X and 200-600, the maximum aperture is similar though. The addition of TC, however, reduces the depth of field compared to using the same lens at the same focal length and distance to subject, and it can be that the smallest step in focus distance that the focus motor can achieve reproducibly is adequate given the depth of field of the lens without TC, but when the TC has been added, the precision may be insufficient. This depends on the implementation of the focusing system in the lens.
3. Optical design, focusing groups, and type of focusing motor(s). Different lenses use different methods of focusing, with some lenses having very light focusing groups and other lenses move the whole optical system in one block. It is often the case that prime lenses have lighter focusing groups that can adjust focus over large distances faster than zooms. Newer and higher-end lenses tend to be more optimized for fast focusing. Some lenses have multiple focusing groups and multiple motors.
Although I would agree that the camera body (including the sensor and processors) has the largest impact on focusing speed and accuracy today, especially in fast action situations, the lens does contribute to the focusing process and has an impact on overall focusing performance.
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
Not knowing the specifics, the lens does contribute to autofocus performance in several ways.
1. Optical quality: aberrations such as longitudinal chromatic aberration can lead the autofocus to hesitate between focusing the different colors. Lenses well corrected for LoCA tend to focus with less hesitation and better reproducibility. The use of a TC can increase aberrations wide open (and leads to a smaller aperture) and thus lead to slightly reduced performance in autofocus.
2. Depth of field. A faster lens gives more light and the distribution of incoming light angle rays is such that the focus is better defined, at least if there are no aberrations. AF benefits from both. (In case of the 100-400/4.5 + 1.4X and 200-600, the maximum aperture is similar though. The addition of TC, however, reduces the depth of field compared to using the same lens at the same focal length and distance to subject, and it can be that the smallest step in focus distance that the focus motor can achieve reproducibly is adequate given the depth of field of the lens without TC, but when the TC has been added, the precision may be insufficient. This depends on the implementation of the focusing system in the lens.
3. Optical design, focusing groups, and type of focusing motor(s). Different lenses use different methods of focusing, with some lenses having very light focusing groups and other lenses move the whole optical system in one block. It is often the case that prime lenses have lighter focusing groups that can adjust focus over large distances faster than zooms. Newer and higher-end lenses tend to be more optimized for fast focusing. Some lenses have multiple focusing groups and multiple motors.
Although I would agree that the camera body (including the sensor and processors) has the largest impact on focusing speed and accuracy today, especially in fast action situations, the lens does contribute to the focusing process and has an impact on overall focusing performance.
Jun 04, 2026 at 04:12 AM
p.16 #3New 100-400 lenses
duncangr wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
No expert here but don't the lens motors play a role in the focus speed too? I have the 200-600 and I don't have issue with the AF speed for what i shoot. But folks say it has the "inferior" motor compared to some other Sony lenses.
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
No expert here but don't the lens motors play a role in the focus speed too? I have the 200-600 and I don't have issue with the AF speed for what i shoot. But folks say it has the "inferior" motor compared to some other Sony lenses.
Jun 04, 2026 at 04:57 AM
p.16 #4New 100-400 lenses
duncangr wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
Jun 04, 2026 at 06:14 AM
p.16 #5New 100-400 lenses
arbitrage wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
But what about adding TC to get same focal length? Do you think 100-400 will still have the edge? If I get the lens I want to use it with TC 75% of the time and without only 25%. Steve Perry's statement on TC made me to cancel my order.
duncangr wrote
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
But what about adding TC to get same focal length? Do you think 100-400 will still have the edge? If I get the lens I want to use it with TC 75% of the time and without only 25%. Steve Perry's statement on TC made me to cancel my order.
Jun 04, 2026 at 06:28 AM
p.16 #6New 100-400 lenses
Pixel Perfect wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.
Jun 04, 2026 at 06:43 AM
p.16 #7New 100-400 lenses
duncangr wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
I'm not implying the lens is independently responsible for the focusing process, but it absolutely has an impact on overall AF performance. The quad XD motors are a substantial upgrade over the dual linear motors of the 200-600.
Also, I should have mentioned my experience with the 200-600 behavior is with the A1ii, which of course is no slouch when it comes to AF. In other words, the camera was certainly not the limiting factor in this combo.
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The...Show more →
I'm not implying the lens is independently responsible for the focusing process, but it absolutely has an impact on overall AF performance. The quad XD motors are a substantial upgrade over the dual linear motors of the 200-600.
Also, I should have mentioned my experience with the 200-600 behavior is with the A1ii, which of course is no slouch when it comes to AF. In other words, the camera was certainly not the limiting factor in this combo.
Jun 04, 2026 at 06:51 AM
p.16 #8New 100-400 lenses
Jemini wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.But what about adding TC to get same focal length? Do you think 100-400 will still have the edge? If I get the lens I want to use it with TC 75% of the time and without only 25%. Steve Perry's statement on TC made me to cancel my order.
Yeah, that is the big mystery. The only way I will know is to test it myself. Steve's review really had me questioning whether this lens would be worth it over a 200-600 which is why I borrowed a friend's 200-600 to remind myself how the lens was on latest FW and on a newer camera (I last owned it during my A9II, A7RIV days).
My dealer just emailed me this morning saying his meeting with Sony yesterday said his supply will meet his demand so he should have one for me if I want it at release time (June 11th). I think I will just go ahead and get it. The days I can shoot are Fri-Sun so don't know if I'll have it for that weekend or not till the following weekend (has to ship across Canada).
TC performance will be the first thing I'm testing. I still have my friend's copy of the 200-600 to do a little side by side testing.
arbitrage wrote
duncangr wrote
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
Yeah, that is the big mystery. The only way I will know is to test it myself. Steve's review really had me questioning whether this lens would be worth it over a 200-600 which is why I borrowed a friend's 200-600 to remind myself how the lens was on latest FW and on a newer camera (I last owned it during my A9II, A7RIV days).
My dealer just emailed me this morning saying his meeting with Sony yesterday said his supply will meet his demand so he should have one for me if I want it at release time (June 11th). I think I will just go ahead and get it. The days I can shoot are Fri-Sun so don't know if I'll have it for that weekend or not till the following weekend (has to ship across Canada).
TC performance will be the first thing I'm testing. I still have my friend's copy of the 200-600 to do a little side by side testing.
Jun 04, 2026 at 08:04 AM
p.16 #9New 100-400 lenses
arbitrage wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.But what about adding TC to get same focal length? Do you think 100-400 will still have the edge? If I get the lens I want to use it with TC 75% of the time and without only 25%. Steve Perry's statement on TC made me to cancel my order.Yeah, that is the big mystery. The only way I will know is to test it myself. Steve's review really had me questioning whether this lens would be worth it over a 200-600 which is why I borrowed a friend's 200-600 to remind myself how the lens was on latest FW and on a newer camera (I last owned it during my A9II, A7RIV days).
My dealer just emailed me this morning saying his meeting with Sony yesterday said his supply will meet his demand so he should have one for me if I want it at release time (June 11th)....Show more →
Can't wait for your findings.
Not surprised that supply meeting demand. The one available in Buy & Sell is still there. It seems many are waiting to see more test results.
Jemini wrote
arbitrage wrote
duncangr wrote
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
My dealer just emailed me this morning saying his meeting with Sony yesterday said his supply will meet his demand so he should have one for me if I want it at release time (June 11th)....Show more →
Can't wait for your findings.
Not surprised that supply meeting demand. The one available in Buy & Sell is still there. It seems many are waiting to see more test results.
Jun 04, 2026 at 08:23 AM
p.16 #10New 100-400 lenses
InFocus2014 wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an...Show more →
By any chance did you try the 2X TC with new 70-200? AF? Sharpness?
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
By any chance did you try the 2X TC with new 70-200? AF? Sharpness?
Jun 04, 2026 at 08:29 AM
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p.16 #11New 100-400 lenses
Jemini wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?
I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
InFocus2014 wrote
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
Jun 04, 2026 at 10:10 AM
p.16 #12New 100-400 lenses
MMP wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and...Show more →
Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TC
Jemini wrote
InFocus2014 wrote
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TC
Jun 04, 2026 at 10:58 AM
p.16 #13New 100-400 lenses
Jemini wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TC
I certainly hope the native 100-400 will be better than the 70-200 + 2X. Just looking at prices alone, the 70-200 + 2X is $3600 ($3300 if you go with the Viltrox 2X) vs the 100-400 at $4300.
If people are paying $1k more and not getting something meaningfully better, this lens will become Sony's biggest flop.
MMP wrote
Jemini wrote
InFocus2014 wrote
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
I certainly hope the native 100-400 will be better than the 70-200 + 2X. Just looking at prices alone, the 70-200 + 2X is $3600 ($3300 if you go with the Viltrox 2X) vs the 100-400 at $4300.
If people are paying $1k more and not getting something meaningfully better, this lens will become Sony's biggest flop.
Jun 04, 2026 at 12:00 PM
p.16 #14New 100-400 lenses
MMP wrote:
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TCI certainly hope the native 100-400 will be better than the 70-200 + 2X. Just looking at prices alone, the 70-200 + 2X is $3600 ($3300 if you go with the Viltrox 2X) vs the 100-400 at $4300.
If people are paying $1k more and not getting something meaningfully better, this lens will become Sony's biggest flop.
Oh I meant the old 100-400/4.5-5.6. Anyway I think if we more use with 100-400 than 70-200 I think it's better with stay with 100-400
Jemini wrote
MMP wrote
Jemini wrote
InFocus2014 wrote
Pixel Perfect wrote
Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
If people are paying $1k more and not getting something meaningfully better, this lens will become Sony's biggest flop.
Oh I meant the old 100-400/4.5-5.6. Anyway I think if we more use with 100-400 than 70-200 I think it's better with stay with 100-400
Jun 04, 2026 at 12:21 PM
p.16 #15New 100-400 lenses
Jemini wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TC
I tested my 100-400/5.6 vs my friend's 70-200/2.8II+2xTC. The 100-400 gave noticeably sharper images and seemed to have a bit faster AF shooting some BIF. However the 70-200II was the first lens I thought the 2xTC did well on. I'd never been happy with it on 400GM or 600GM. Of course the 300GM does the best with it.
MMP wrote
Jemini wrote
InFocus2014 wrote
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
I tested my 100-400/5.6 vs my friend's 70-200/2.8II+2xTC. The 100-400 gave noticeably sharper images and seemed to have a bit faster AF shooting some BIF. However the 70-200II was the first lens I thought the 2xTC did well on. I'd never been happy with it on 400GM or 600GM. Of course the 300GM does the best with it.
Jun 04, 2026 at 02:42 PM
p.16 #16New 100-400 lenses
arbitrage wrote:
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TCI tested my 100-400/5.6 vs my friend's 70-200/2.8II+2xTC. The 100-400 gave noticeably sharper images and seemed to have a bit faster AF shooting some BIF. However the 70-200II was the first lens I thought the 2xTC did well on. I'd never been happy with it on 400GM or 600GM. Of course the 300GM does the best with it.
Thank you Geoff. This answers my question. I tried two copies of 100-400 and both were worse than 200-600 and even 70-350mm (DX). 70-350 had less focus breathing compared to 100-400. So I think 100-400 has high copy variation. I might rent these myself
Jemini wrote
MMP wrote
Jemini wrote
InFocus2014 wrote
Pixel Perfect wrote
Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
Thank you Geoff. This answers my question. I tried two copies of 100-400 and both were worse than 200-600 and even 70-350mm (DX). 70-350 had less focus breathing compared to 100-400. So I think 100-400 has high copy variation. I might rent these myself
Jun 04, 2026 at 02:58 PM
p.16 #17New 100-400 lenses
Jemini wrote:
By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TCI tested my 100-400/5.6 vs my friend's 70-200/2.8II+2xTC. The 100-400 gave noticeably sharper images and seemed to have a bit faster AF shooting some BIF. However the 70-200II was the first lens I thought the 2xTC did well on. I'd never been happy with it on 400GM or 600GM. Of course the 300GM does the best with it.Thank you Geoff. This answers my question. I tried two copies of 100-400 and both were worse than 200-600 and even 70-350mm (DX). 70-350 had less focus breathing compared to 100-400. So I think 100-400 has high copy variation. I might rent these myself
I will say that my comparison was done with my second copy of the 100-400 and my second (current) copy is amazingly sharp. Even with the 1.4TC it is sharper than the three 200-600 copies I've compared it against.
My 1st 100-400 was about equal to my 200-600 at say the 400mm mark and the 200-600 was better than it at 560mm.
arbitrage wrote
Jemini wrote
MMP wrote
Jemini wrote
InFocus2014 wrote
I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
I will say that my comparison was done with my second copy of the 100-400 and my second (current) copy is amazingly sharp. Even with the 1.4TC it is sharper than the three 200-600 copies I've compared it against.
My 1st 100-400 was about equal to my 200-600 at say the 400mm mark and the 200-600 was better than it at 560mm.
Jun 04, 2026 at 05:13 PM
p.16 #18New 100-400 lenses
arbitrage wrote:
I have the 2x and the 70-200ii. There is a definite hit to sharpness, and a much lesser hit to contrast, but it's absolutely nothing that makes me hesitate to use it for my purposes (soccer/football). If I were shooting birds/wildlife, I would probably want something sharper. AF is still very good in my experience, but I can tell when the TC is attached. In daylight, it's just a tad slower to lock onto an eye and it just isn't as "sticky" when there are multiple players running in/out of the frame. Night games are more of a challenge and I usually end up ditching the 2x.
I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.Thank you very much for the detailed observation. Do you think 100-400 would be better than 70-200+2X ? I know earlier versions of 70-200 was not that great. New one seems to be way better with TCI tested my 100-400/5.6 vs my friend's 70-200/2.8II+2xTC. The 100-400 gave noticeably sharper images and seemed to have a bit faster AF shooting some BIF. However the 70-200II was the first lens I thought the 2xTC did well on. I'd never been happy with it on 400GM or 600GM. Of course the 300GM does the best with it.Thank you Geoff. This answers my question. I tried two copies of 100-400 and both were worse than 200-600 and even 70-350mm (DX). 70-350 had less focus breathing compared to 100-400. So I think 100-400 has high copy variation. I might rent these myselfI will say that my comparison was done with my second copy of the 100-400 and my second (current) copy is amazingly sharp. Even with the 1.4TC it is sharper than the three 200-600 copies I've compared it against.
My 1st 100-400 was about equal to my 200-600 at say the 400mm mark and the 200-600 was better than it at 560mm.
I understand. Both my 100-400 was equal or slightly worse than 200-600 at 400mm. Actually I dropped my 200-600 and repaired and fine tuned by authorized center. Not sure if it improved the sharpness. Anyhow it was very sharp. The 70-350 is wonder little lens.
A1 and 70-350mm Sony lens
Jemini wrote
arbitrage wrote
Jemini wrote
MMP wrote
Jemini wrote
By any chance did you try the 2X TC with new 70-200? AF? Sharpness?I'd say my keeper rate in the day with bare lens is 95+% and drops to about 85% with the 2X. Bare lens at night is still around 90-95%, but when you add the 2X to the poor lighting, I'm probably at or below 70%.
FWIW, I'm actually still impressed with 2x on the 70-200 because I consider my typical shooting location to be challenging with poor lighting and very busy backgrounds. If the 2x performs at least as well on the 100-400, I'd be happy. If it's even slightly better, I'd be ecstatic.
My 1st 100-400 was about equal to my 200-600 at say the 400mm mark and the 200-600 was better than it at 560mm.
I understand. Both my 100-400 was equal or slightly worse than 200-600 at 400mm. Actually I dropped my 200-600 and repaired and fine tuned by authorized center. Not sure if it improved the sharpness. Anyhow it was very sharp. The 70-350 is wonder little lens.
A1 and 70-350mm Sony lens
Jun 04, 2026 at 07:39 PM
p.16 #19New 100-400 lenses
arbitrage wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.From the samples I've seen, the IQ is better than my 200-600. Not blowing it out of the water, but it's better. That's a win because the 200-600 already has remarkable IQ for a telephoto zoom in that range. The AF of the 200-600 is good, but it's not great. It struggles during soccer and football when the light gets dim. When you add a TC in poor light, AF gets pretty bad and borderline useless. The AF/tracking of the 100-400 is going to run circles around the 200-600 under all conditions, with and without a TC.
.Your wording above seems to imply the lens struggles with focussing - the lens doesn't do any focussing - that's all done by the camera. The lens just responds to requests from the camera to move the focus point, it's the camera that determines when things are 'in focus'.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).Equalizing the cameras and using the A1II for both, I shot swallows for an hour going back and forth between the 200-600 and the 300/2xTC. The 300/2xTC was way faster at focusing despite the 2xTC being on it. The hit rate was significantly higher. I don't think we can say the 1/3 stop of light advantage was the sole factor.
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
My hope too. 200-600G is old usm style single motor. I find it hard to believe the new 100-400 with 4 XDL motors even with 1.4x can't drive the focus elements faster.
I'm not fussed about IQ. It's GM lens and I know IQ even with 1.4x will be excellent. Even it it matches my 200-600 I'll be happy as I have a nice sharp copy and no complaints about IQ. My biggest gripe is the near useless OS for video. The new 100-400 is much better in that regard.
duncangr wrote
MMP wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
.
The 100-400 at 560 f/6.3 is going to let the same amount of light in as the 200-600 at 600 so I would expect the camera will have the same problem with focussing.
Just compare the performance of the 200-600 with A9iii attached to that of the 200-600 with A1 attached. The 200-600 seems like a whole other lens suddenly (with the A9iii).
The lens' AF motors play a big part in responding to the focusing instructions provided by the camera.
This is my hope with the 100-400 vs the 200-600....that the 4x linear motors will improve focusing over the 200-600.
My hope too. 200-600G is old usm style single motor. I find it hard to believe the new 100-400 with 4 XDL motors even with 1.4x can't drive the focus elements faster.
I'm not fussed about IQ. It's GM lens and I know IQ even with 1.4x will be excellent. Even it it matches my 200-600 I'll be happy as I have a nice sharp copy and no complaints about IQ. My biggest gripe is the near useless OS for video. The new 100-400 is much better in that regard.
Jun 04, 2026 at 09:27 PM
p.16 #20New 100-400 lenses
Jemini wrote:
On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.Not a snowball's chance in hell with the 2x it gets close to the 400-800 IMO. 200-600 + 1.4x is week at 840mm despite being very good sans TC. 100-400 + 1.4x @560 appears about as good as the bare 200-600 @600. I expect 100-400 + 2x @800 to be similar to 200-600 + 1.4x @ 840.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.I agree. I almost sold my 2x converter since, for me, the IQ was unacceptable with every telephoto zoom that I tried it with. Then I acquired the GM 300mm f2.8 and almost had to pinch myself when I critically viewed IQ with the converter, as it was surprisingly good (better than my 200-600mm). I expect to acquire the new 100-400mm, in the near future, but am in no hurry to test it with the 2x converter, as I expect that I will not like the results. As note, I went through a number of 2x converters to select an optimal one.By any chance did you try the 2X TC with new 70-200? AF? Sharpness?
Yes. I was not happy with the sharpness. I found better IQ by using the 1.4X and then just cropping.
InFocus2014 wrote
Pixel Perfect wrote
DWOfPaul wrote
I am still having a hard time deciding on this lens. On one hand, I want it. Having a 100-400mm f4.5 sounds great for subject separation and when the light gets low. Add a TC 1.4 and you get a 140-560mm f6.3 that should be just as good as the 200-600mm f6.3. It will also be a bit lighter, have a bit bigger zoom range, and take front and rear filters. Add a TC 2x and you have a 200-800mm f9, which is hopefully as good as the 400-800mm at 800mm (sounds like we need a bit more testing here to know for sure) and will definitely be lighter and have a much bigger zoom range.On the other hand, it's hard to say from the initial reviews if it's substantially better than the 200-600mm and 400-800mm. Adding a 4lb and 4k+ lens that doesn't at least fully replace my 200-600mm is a hard sell.
As for the f4.5 aperture, if this lens were a 7lb+ 8k+ f4 zoom, I would not be interested in it at all. So I actually see the f4.5 as an advantage in this case. The only thing that may have added interest to me is if they added an internal TC, even if it added like 1/2 pound to the weight and a few hundred to the cost, if it improved IQ vs an external TC it would have been a value add to me.
The only Sony lens that does very well with the 2x is the 300 f/2.8. Even the 400 f/2.8 and 600 f/4 with 2x are noticeably weaker than Nikon's equivalents and behind the 300.
Yes. I was not happy with the sharpness. I found better IQ by using the 1.4X and then just cropping.
Jun 05, 2026 at 05:20 AM