Steve Spencer wrote:
I am not sure what you want to see. Do you want to see a Sony 42 MP sensor compared to a Sony 60MP sensor? If so, see Fred's thread comparing the Sony A7r IIIa with the SonyA7r IV linked earlier in this thread. To me I can see the effect of the increased resolution. I wouldn't call the effect big, but it is there when viewed at the magnification level Fred provided. My own subjective evaluation is that the difference although perceptible isn't that important to me, but others can easily feel differently.
If you want to compare a FF 60 or 67 MP sensor to a FF 100 MP sensor, obviously no one can do that. So, I'm not sure what exactly it is you want to see that hasn't been shown and could be shown....Show more →
The difference between 42 and 60MP was large. At first it was annoying how much noise the a7rIV had in comparison to the a7rIII, but with modern NR it's no big deal and NR likes pixels. Of course 67 vs 60MP is only 4% or so but nobody is upgrading from an a7rIV/a7rV for that reason.
kimmeisinger wrote:
Hey all...I am a bird photographer who has really enjoyed her A1's. But I have realized I really need pre-capture capabilities. My only question is a used A1-II or the new A7RVI. I have the 600mm, 300mm and am considering the 100-400 f4.5 and leaving the 300mm at home for international trips. I tested the 400-800 which was sharp but heavy. I have shoulder replacements coming up so trying to lighten the load. Would those who are reading this thread and do a lot of birds, chime in with their opinion and why. I like to learn but technical I am not. ...Show more →
A1ii - I am not sure the A7RM6 pre-capture is at quite the same level as the A1ii. In my limited use it seems to not be quite as reliable as the A1ii pre-capture. Having said that lots of people seem to have limited success with even the A1ii pre-capture so ymmv with the A1ii.
If you shoot a lot of action then stick with the A1/A1ii or A9iii.
If you have more than one camera and one will be an A1/A1ii or A9iii then as a second camera the A7RM6 is excellent for stills and larger birds in flight - where I want to capture the absolute maximum fine detail - perhaps even using mechanical shutter.
Personally I primarily use an A9iii for small bird/fast action and A7RM6 for everything else.
I prefer the higher resolution cameras for larger birds/animals and larger birds in flight where the fine feather/fur detail is small in comparison to the animal/bird. Lower resolution cameras don't capture the fine detail on such large subjects very well.
Mark Smith, one of Sonys ambassadors posted this video the other day. He makes a remarkable statement at 8:25 or so about the AF on the A7R6 besting the A1 II.....🤔
James Burden wrote:
Mark Smith, one of Sonys ambassadors posted this video the other day. He makes a remarkable statement at 8:25 or so about the AF on the A7R6 besting the A1 II.....🤔
I would agree the subject detection and AF may be a little better, just haven't found that translates quite so well on the pre-capture though.
A video on a7rvi that discusses AF that I missed before and noticed it today. It is in German but youtube's AI voice translation is usable on it or use translated subtitles.
The photographer uses standardized bird in flight test using a stuffed bird sliding over a rope using the same lens.
Summary of the results for various cameras:
- a9iii: 117 or 118 of 120 (97-98%) sharp.
- a1 (probably the a1ii that is mentioned in older video for a7v AF test): 27 or 28 of 30 (90-93%) sharp.
- mid range Sony cameras had always 50 to 60% of sharp shots (out of 10).
- a7v: 80% of 30 sharp.
- a7rvi: 86% of 30 sharp. Claims specifically that it is better than a7v. Claims that part of difference over say a9iii is that small misfocus is more visible with higher pixel density.
Percentages are based on focused category out of focused / slight misfocus / not focused (this information was in older a7v video where the test setup is explained more in depth).
Note that the movement that is tested is predictable. Results with less predicable movement might be different.
In comments section (discussion with user yushi213 and with user Urban.nature.wildlife.a7) it looks like he is shooting almost always in Compressed HQ and unaware (at the time) that Compressed (not Compressed HQ) is need for 60 AF calculations per second on a7rvi. So maybe the a7rvi result could be even better with just Compressed raws.
There is also one thing discussed in comments by user anatolkoch3154: that scan speed of sensor determines number of AF calculations per second. I have seen this assumption in other discussions as well but I think it is more complex that that.
A7rvi can do about 19.6ms in 14 bit photo mode and about 14ms in 12 bit photo mode, but to do the AF you do not have to read all sensor. There AF rows and non-AF rows (in some cameras like a7iii the AF rows under certain light and in camera reflections with some lenses like 85/1.8G become visible https://www.dpreview.com/news/6974141509/sony-striping-heres-the-fix and they were like only about 1 AF row per 10 rows on that camera). You need to read just AF rows for AF which can be much faster. For subject detection and following subject you need to read most of the sensor (also for viewfinder/monitor), but you do not have to do it in high resolution mode. As tested by DPReview and Optyczne.pl the video modes in 4k with no crop can be faster, around 7ms (those are 16:9 but there needs to be some video mode for EVF with full 3:2 aspect so that can be a bit slower, but not as slow as 14ms) and even faster in FHD (3.6ms). In fact a7rvi has some video modes faster than a1ii if you compare the tables in these pages: a7rvi video modes (Optyczne.pl) a1ii video modes (Optyczne.pl)
The video is here, AF test at 33m 26s:
?t=2006
Jul 05, 2026 at 05:43 AM
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jtra wrote:
A video on a7rvi that discusses AF that I missed before and noticed it today. It is in German but youtube's AI voice translation is usable on it or use translated subtitles.
The photographer uses standardized bird in flight test using a stuffed bird sliding over a rope using the same lens.
Summary of the results for various cameras:
- a9iii: 117 or 118 of 120 (97-98%) sharp.
- a1 (probably the a1ii that is mentioned in older video for a7v AF test): 27 or 28 of 30 (90-93%) sharp.
- mid range Sony cameras had always 50 to 60% of sharp shots (out of 10).
- a7v: 80% of 30 sharp.
- a7rvi: 86% of 30 sharp. Claims specifically that it is better than a7v. Claims that part of difference over say a9iii is that small misfocus is more visible with higher pixel density.
Percentages are based on focused category out of focused / slight misfocus / not focused (this information was in older a7v video where the test setup is explained more in depth).
Note that the movement that is tested is predictable. Results with less predicable movement might be different.
In comments section (discussion with user yushi213 and with user Urban.nature.wildlife.a7) it looks like he is shooting almost always in Compressed HQ and unaware (at the time) that Compressed (not Compressed HQ) is need for 60 AF calculations per second on a7rvi. So maybe the a7rvi result could be even better with just Compressed raws.
There is also one thing discussed in comments by user anatolkoch3154: that scan speed of sensor determines number of AF calculations per second. I have seen this assumption in other discussions as well but I think it is more complex that that.
A7rvi can do about 19.6ms in 14 bit photo mode and about 14ms in 12 bit photo mode, but to do the AF you do not have to read all sensor. There AF rows and non-AF rows (in some cameras like a7iii the AF rows under certain light and in camera reflections with some lenses like 85/1.8G become visible https://www.dpreview.com/news/6974141509/sony-striping-heres-the-fix and they were like only about 1 AF row per 10 rows on that camera). You need to read just AF rows for AF which can be much faster. For subject detection and following subject you need to read most of the sensor (also for viewfinder/monitor), but you do not have to do it in high resolution mode. As tested by DPReview and Optyczne.pl the video modes in 4k with no crop can be faster, around 7ms (those are 16:9 but there needs to be some video mode for EVF with full 3:2 aspect so that can be a bit slower, but not as slow as 14ms) and even faster in FHD (3.6ms). In fact a7rvi has some video modes faster than a1ii if you compare the tables in these pages: a7rvi video modes (Optyczne.pl) a1ii video modes (Optyczne.pl)
The video is here, AF test at 33m 26s:
?t=2006 ...Show more →
Let me summarize these results with the full numbers below and some reasonable assumptions:
A9 III 117 or 118 out of 120 (I assume this was 1 second at 120 fps) let's call it 117.5 out of 120 the equivalent of 29 out of 30.
A1 II 28 or 29 out of 30, let's call it 28.5 out of 30 (I assume this and all the out of 30 numbers are 30 fps)
A7r VI 26 out of 30
A7 V 24 out of 30
midrange Sony whatever that is, but presumably A7 series before this camera, so let's say A7r V and A7 iV 50 to 60 percent let's call that 16.5 out of 30, but these cameras cannot shoot at 30 fps and in fact max out at 10 fps so in 1 second 5.5 out of 10.
So in one second of burst shooting we get:
A9 III - 117.5 out of 120
A1 II - 28.5 out of 30
A7r VI - 26 out of 30
A7 V - 24 out of 30
A7r V and A7 IV - 5.5 out of 10
So for this target and this test I think we can safely conclude that the A9 III gets a lot more shots in one second of burst shooting than any of the other cameras. A lot of that is due to the much faster fps, but might be due to better focus accuracy too, although the data on that is a lot less clear especially compared to the A1 II.
I think we can also conclude that in one second of burst shooting the A7r V and A7 IV, although they can probably get this shot, with one second of burst shooting might miss it and especially so if they have less than a second of shooting. The newer generation is clearly a step up, but much of that is due to faster frames per second, but difference in AF accuracy are probably there too.
The A1 II, A7r VI, and A7 V has more subtle differences. There is some chance the A1 II is better than the A7r VI and some chance the A7r VI is better than the A7V and a better chance the A1 II is better than the A7 V, but there really isn't enough data to be sure of any of these differences. Repeating the test, let's say 10 or more times, would obviously get us a lot more data and would probably allow us to asses whether these more subtle differences are in fact there. That would be a lot to ask from the poster of the video, who has already done a lot, but it could be done.
James Burden wrote:
It seems from your impressive Flickr portfoliio you enjoy more than just birds. You mentioned A1's in the plural so I suspect you have a back up body. I ended up first with the A1 II for 30 FPS and pre-capture as I already had an A7R5 but had just started with BIF photography. I also now have the A7R6 and feel like they are very complimentary to each other and I have no desire to make any changes. That being said if I were doing that again with the A7R6 now available I don't know if I would have gotten the A1 II. It's very close in capability although the A1 II is surely faster for some genres albeit at the expense on some resolution. Read through this thread and you'll get many, many opinions/tests/charts and equations to complicate your choice. YMMV.... ...Show more →
Thank you so much for your kindness and thoughtful reply James. I am leaning towards the R6. Yes, I have two A-1s and I do like to do various types of nature photography but have a lot of focus on birds.
duncangr wrote:
A1ii - I am not sure the A7RM6 pre-capture is at quite the same level as the A1ii. In my limited use it seems to not be quite as reliable as the A1ii pre-capture. Having said that lots of people seem to have limited success with even the A1ii pre-capture so ymmv with the A1ii.
If you shoot a lot of action then stick with the A1/A1ii or A9iii.
If you have more than one camera and one will be an A1/A1ii or A9iii then as a second camera the A7RM6 is excellent for stills and larger birds in flight - where I want to capture the absolute maximum fine detail - perhaps even using mechanical shutter.
Personally I primarily use an A9iii for small bird/fast action and A7RM6 for everything else.
I prefer the higher resolution cameras for larger birds/animals and larger birds in flight where the fine feather/fur detail is small in comparison to the animal/bird. Lower resolution cameras don't capture the fine detail on such large subjects very well....Show more →
You have named what I chase relentlessly....detail in fur/feathers. Thank you for sharing what you have found useful and your concern...the pre-capture A 1ii vs. RM6. I do have two A1's. I am leaning heavily for the RM6 for that detail and will just accept what is probably a less often needed....pre-capture. Thank you again for sharing your experiences!
kimmeisinger wrote:
You have named what I chase relentlessly....detail in fur/feathers. Thank you for sharing what you have found useful and your concern...the pre-capture A 1ii vs. RM6. I do have two A1's. I am leaning heavily for the RM6 for that detail and will just accept what is probably a less often needed....pre-capture. Thank you again for sharing your experiences!
Many have demonstrated that the A7R6 is very capable of capturing all but the most extreme cases of fast/erratic movement, as long as you aren’t taking pictures at high shutter speeds of propellers/humming birds. So, the most relevant issue here is the discussion regarding sensor resolution limited by lens resolution and this is certainly the case with sensors of 50Mpix and greater with modern GM lenses. So, the answer is that there is a greater improvement in fine detail, microcontrast moving from a 37 to 50Mpix sensor when compared to the move from 50 to 67Mpix. Likely, the only way to determine if this small improvement is worth the cost of a new body is to purchase from a vendor with a good return policy and purchase when you have a relevant shoot/trip scheduled. Of course, seeing a difference also depends upon how you create/display and view the image. In short, the answer isn’t to be found here. BTW.. I love your work displayed on Flickr. You have made the best of your equipment.. thanks for sharing.
To summarize: The evidence is strongly suggesting that the high resolution A7r6 performs very well with many subjects that might have called for an A1ii or A9iii in the past.
bwcolor wrote:
Many have demonstrated that the A7R6 is very capable of capturing all but the most extreme cases of fast/erratic movement, as long as you aren’t taking pictures at high shutter speeds of propellers/humming birds. So, the most relevant issue here is the discussion regarding sensor resolution limited by lens resolution and this is certainly the case with sensors of 50Mpix and greater with modern GM lenses. So, the answer is that there is a greater improvement in fine detail, microcontrast moving from a 37 to 50Mpix sensor when compared to the move from 50 to 67Mpix. Likely, the only way to determine if this small improvement is worth the cost of a new body is to purchase from a vendor with a good return policy and purchase when you have a relevant shoot/trip scheduled. Of course, seeing a difference also depends upon how you create/display and view the image. In short, the answer isn’t to be found here. BTW.. I love your work displayed on Flickr. You have made the best of your equipment.. thanks for sharing. ...Show more →
Thank you for the understanding you have provided on fine detail/microcontrast improvement with increasing Mpix 50-67 range. These are the things that escape me. And for the way to think through this. Details are important to me as I plan to print images to cover the space over a couch when I can no longer travel at the level I am over the next handful of years. So it sounds like a very small shift. I just returned from a Common Loon shoot and one of the A1's locked up during the shoot twice. And the other A1 completely went down in Australia 10/2025 needing a mother board replacement. The A1's are aging, hence the interest in a newer camera. I do have a trip to Brazil's Atlantic Rainforest shoot coming up in August and it includes some hummingbirds. I'll keep reading and comparing the A1ii and the A7RVI. Thank you for stopping by my Flikr page!
It would be interesting to see a real-life comparison between the A1ii and A7Rvi on both pre-AF functionality and the actual differences in the level of fine detail captured from each. Throw in a realistic DR comparison at the same time 🤷🏼
