This topic is in the 2015 archive. You can read it and like its posts here. It is read only.
Archive 2015A thinner sensor stack may be possible after all!
p.13 #1A thinner sensor stack may be possible after all!
^^^ Steve, would you even drink their light beer? 
Feb 07, 2015 at 05:50 PM
p.13 #2A thinner sensor stack may be possible after all!
Steve Spencer wrote:
But I suspect we will see sometime soon.Where have you read that? Everything that I have seen from Zeiss suggests that they were designed specifically for the cover glass of the A7 series cameras.I don't think there is any evidence, but I do believe the same. The performance in the corners of the FE35 and especially the FE24-70 is just not good enough for Zeiss, and I suspect that they knew that Sony had used a cheap, thick sensor glass covering in their initial models, to keep prices down and increase the chance of success for the system as a whole. I think that they then designed lenses which performed acceptably on such glass, but which will shine, or at least do much better, when Sony releases higher-speced models.But the FE 35 and FE 24-70 are Sony/Zeiss likely designed by Sony. And if you look at the ZM 35 f/2 on the modified cameras it looks a lot like the Loxia 35 on the unmodified cameras, so I don't think the Loxia lenses will do better on the modified cameras and I certainly don't think the Sony/Zeiss FE lenses will do better and there is a little evidence there. In Roger's imatest results, which are close up the FE lenses did just a tad worse and this deterioration should get a bit worse at infinity.Of course the ZM 35/2 is designed for film and the best you will see from it digitally is on the M9, not A7.mod. The Loxia 35/2 is certainly not up to those standards on any stock A7 series camera, and most seem to feel it is bested by the FE 35/2.8. I don't think expectations have been met with the 35 loxia for many potential buyers.
Why? How could this be? As Carsten notes, the 2470 has also been a real disappointment, though it's not terrible of course, but not what we'd hoped for and certainly not for the price.
So, Steve you and I can guess about who thought what, and what was designed for what, but those are things we can never know.
However, I will bet you a six pack of nice beer, loser funded via paypal, not to exceed 10USD, that the Loxia 35 is better on the A7.mod or A7r.mod. Also I suspect the 2470 will be better too, but let's stick to the Loxia.
Better will simply mean edges and corners at some apertures. without terrible loss in the center.
I do agree with you and Michael that the FE35 and 55 will be a bit worse. But I agree with Carsten that the Zeiss 2470 and Loxia were not "properly designed" for the thick cover.
Michael, I would add that a thick cover for M43 is no problem because you don't have near the angles going with that tiny sensor. In fact ALT FF glass seems fine on the M43, abeit, cropped.That's a great bet, but we better make it 15 dollars. We take our beer seriously here in Canada
Of course we don't know for sure how it will turn out, but in my view Zeiss screwed up if the Loxia don't work best with the stock cover glass.
And I never liked FF glass on m4/3rds that much. It just didn't look that great, but many people do.
OK we're on 15USD paypaled for beverage of choice, for 15USD I'll find a red
, and you will be able to get good beer
Winner to be arbited by the community here, good?
Tried to test the Elmarit 28 V3 today, but the weather....
DSC01121 by unoh7, A7M Sonnetar @f/1.2ish
DSC01124 by unoh7, Elmarit 28 V3
Basically from what I see it's better but smoked by the 28 cron at every aperture.
Edited on Feb 07, 2015 at 06:09 PM · View previous versions
uhoh7 wrote
Steve Spencer wrote
carstenw wrote
Steve Spencer wrote
uhoh7 wrote
I've read just the opposite, the reason why the FE35/2.8 basically outperforms the Loxia on the A7 is that perhaps Zeiss was not ready to fully commit to such extremes. My reasoning is: they went a aways in the thick CG direction, away from the film plane, and that just might put those lenses right in the sweet spot for the Kolari thickness.But I suspect we will see sometime soon.
Why? How could this be? As Carsten notes, the 2470 has also been a real disappointment, though it's not terrible of course, but not what we'd hoped for and certainly not for the price.
So, Steve you and I can guess about who thought what, and what was designed for what, but those are things we can never know.
However, I will bet you a six pack of nice beer, loser funded via paypal, not to exceed 10USD, that the Loxia 35 is better on the A7.mod or A7r.mod. Also I suspect the 2470 will be better too, but let's stick to the Loxia.
Better will simply mean edges and corners at some apertures. without terrible loss in the center.
I do agree with you and Michael that the FE35 and 55 will be a bit worse. But I agree with Carsten that the Zeiss 2470 and Loxia were not "properly designed" for the thick cover.
Michael, I would add that a thick cover for M43 is no problem because you don't have near the angles going with that tiny sensor.
In fact ALT FF glass seems fine on the M43, abeit, cropped.Of course we don't know for sure how it will turn out, but in my view Zeiss screwed up if the Loxia don't work best with the stock cover glass.
And I never liked FF glass on m4/3rds that much. It just didn't look that great, but many people do.
OK we're on 15USD paypaled for beverage of choice, for 15USD I'll find a red
, and you will be able to get good beer Winner to be arbited by the community here, good?
Tried to test the Elmarit 28 V3 today, but the weather....
DSC01121 by unoh7, A7M Sonnetar @f/1.2ish
DSC01124 by unoh7, Elmarit 28 V3
Basically from what I see it's better but smoked by the 28 cron at every aperture.
Edited on Feb 07, 2015 at 06:09 PM · View previous versions
Feb 07, 2015 at 06:02 PM
p.13 #3A thinner sensor stack may be possible after all!
"But, again, all glass designed for film (no cover stack) will improve. This is what we are seeing and the only question is 'how much' on any particular lens."
Zeiss, Sony, Canon, Nikon and Zeiss might all be interested - can the evidence for the above be published for them and others to review?
Zeiss, Sony, Canon, Nikon and Zeiss might all be interested - can the evidence for the above be published for them and others to review?
Feb 07, 2015 at 06:02 PM
p.13 #4A thinner sensor stack may be possible after all!
Ok you might be able to tell something from this one Elmarit 28 V3 f/8. But Derek suspects this lens may be decentered, so another copy may do better. Obviously light is bad and I had to bring up some levels so there is some noise too.
A7m_Elmarit28_v3_f8 by unoh7, on Flickr
Click Here for Full
Derek, what do you think?
A7m_Elmarit28_v3_f8 by unoh7, on Flickr
Click Here for Full
Derek, what do you think?
Feb 07, 2015 at 06:23 PM
p.13 #5A thinner sensor stack may be possible after all!
philip_pj wrote:
"But, again, all glass designed for film (no cover stack) will improve. This is what we are seeing and the only question is 'how much' on any particular lens."
Zeiss, Sony, Canon, Nikon and Zeiss might all be interested - can the evidence for the above be published for them and others to review?
...or they might not be interested at all since they would rather sell everyone new lenses.
"But, again, all glass designed for film (no cover stack) will improve. This is what we are seeing and the only question is 'how much' on any particular lens."
Zeiss, Sony, Canon, Nikon and Zeiss might all be interested - can the evidence for the above be published for them and others to review?
...or they might not be interested at all since they would rather sell everyone new lenses.
Feb 07, 2015 at 06:28 PM
p.13 #6A thinner sensor stack may be possible after all!
Charlie, I really like all the shots in your album with the 28 Elmarit V3. I have had the 28 Cron Asph, and yes it is sharp, but I did not like it on the M240. Yet on the M9 it was very good IMO. Of course for landscapes you have a different criteria. I always found the 28 Cron Asph on the streets was almost too harsh, depending on the lighting. In lower level and contrast lighting the 28 Cron Asph was excellent.
I love the rendering and look with the 28 Elmarit V3. I feel this lens will work great for B&W conversions
I love the rendering and look with the 28 Elmarit V3. I feel this lens will work great for B&W conversions
Feb 07, 2015 at 06:49 PM
p.13 #7A thinner sensor stack may be possible after all!
uhoh7 wrote:
Ok you might be able to tell something from this one Elmarit 28 V3 f/8. But Derek suspects this lens may be decentered, so another copy may do better. Obviously light is bad and I had to bring up some levels so there is some noise too.
Derek, what do you think?
the lens looks a little bit better, but not as big an improvement some of the more modern lenses.
it still looks worse on the left side than the right. the difference would probably be more noticeable at larger apertures.
Ok you might be able to tell something from this one Elmarit 28 V3 f/8. But Derek suspects this lens may be decentered, so another copy may do better. Obviously light is bad and I had to bring up some levels so there is some noise too.
Derek, what do you think?
the lens looks a little bit better, but not as big an improvement some of the more modern lenses.
it still looks worse on the left side than the right. the difference would probably be more noticeable at larger apertures.
Feb 07, 2015 at 07:06 PM
p.13 #8A thinner sensor stack may be possible after all!
charles.K wrote:
Charlie, I really like all the shots in your album with the 28 Elmarit V3. I have had the 28 Cron Asph, and yes it is sharp, but I did not like it on the M240. Yet on the M9 it was very good IMO. Of course for landscapes you have a different criteria. I always found the 28 Cron Asph on the streets was almost too harsh, depending on the lighting. In lower level and contrast lighting the 28 Cron Asph was excellent.
I love the rendering and look with the 28 Elmarit V3. I feel this lens will work...Show more →
I think many share your view, but I've been very impressed by Ron's work with the 28 Cron on the 240. It's a different lens than with the M9, but seems to perform great right across the frame.
I think the f/8 shot above suggests the v3, esp a great copy, can be pretty respectable, and it's certainly very nice closer in or with shots that don't need the edges.
Here we go around f/8 or even smaller and that one bar is quite crisp right to the edge:
DSC01182 by unoh7, on Flickr
and here at f/4
DSC01150 by unoh7, on Flickr
As you know there are 5 versions of the elmarit 28. If I could pick just one, it would be the v4, which I don't own.
Charlie, I really like all the shots in your album with the 28 Elmarit V3. I have had the 28 Cron Asph, and yes it is sharp, but I did not like it on the M240. Yet on the M9 it was very good IMO. Of course for landscapes you have a different criteria. I always found the 28 Cron Asph on the streets was almost too harsh, depending on the lighting. In lower level and contrast lighting the 28 Cron Asph was excellent.
I love the rendering and look with the 28 Elmarit V3. I feel this lens will work...Show more →
I think many share your view, but I've been very impressed by Ron's work with the 28 Cron on the 240. It's a different lens than with the M9, but seems to perform great right across the frame.
I think the f/8 shot above suggests the v3, esp a great copy, can be pretty respectable, and it's certainly very nice closer in or with shots that don't need the edges.
Here we go around f/8 or even smaller and that one bar is quite crisp right to the edge:
DSC01182 by unoh7, on Flickr
and here at f/4
DSC01150 by unoh7, on Flickr
As you know there are 5 versions of the elmarit 28. If I could pick just one, it would be the v4, which I don't own.
Feb 07, 2015 at 07:12 PM
p.13 #9A thinner sensor stack may be possible after all!
In response to some earlier discussion on this thread about infinity focus on the mod, I suspect most who have alt lens experience understand that there is a dilemma when deciding on the 'proper' infinity focus adjustment. Remember, the sensor does have to be moved in the mod, since the thinner stack has a shorter optical path length.
I normally use the Voigtlander VM-E Close Focus adapter on the A7, and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses. (This is the same as the camera before the mod.)
However, for the project I recently got a Novoflex NEX/LEM and, with that adapter, the infinity focus is bang-on with three lenses that I know are properly calibrated (two essentially new - a 24mm Elmar 3.8 and 90mm Summarit - and a 50mm Summicron V5 that just came back from Leica for a CLA). I didn't have the Novoflex before the mod, so can't comment on that.
This test shows me that even the two most well-respected adapters don't appear to be the same. (I can't find my micrometer at the moment, but will post the measurements when I put my hands on it.) And let's not even talk about the legions of Ebay cheapies.
So, the dilemma... What should Kolari adjust focus for? The current mod appears perfect with the Novoflex - at least on properly adjusted lenses. It will be interesting to run through my larger collection and see if they are all acceptable with this adapter. I'll report on that when I have time.
With the VM-E there is some room for a lens to be off and still hit infinity. With a lot of 50+ year old lenses out there and in my collection (Leica, Canon, Nikor, etc.) I imagine some might have issues on the Novoflex, so the "safety margin" on the VM-E might be welcome. And, if those lenses are off with the Novoflex (which, again, seems properly calibrated on my A7M), they are going to be off on the Leica rangefinder, too.
So... which adapter are you using? I think a survey would be valuable as we continue to develop these modifications. If people want to PM me with their adapter choices, I'll compile some info and publish he results.
Michael
I normally use the Voigtlander VM-E Close Focus adapter on the A7, and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses. (This is the same as the camera before the mod.)
However, for the project I recently got a Novoflex NEX/LEM and, with that adapter, the infinity focus is bang-on with three lenses that I know are properly calibrated (two essentially new - a 24mm Elmar 3.8 and 90mm Summarit - and a 50mm Summicron V5 that just came back from Leica for a CLA). I didn't have the Novoflex before the mod, so can't comment on that.
This test shows me that even the two most well-respected adapters don't appear to be the same. (I can't find my micrometer at the moment, but will post the measurements when I put my hands on it.) And let's not even talk about the legions of Ebay cheapies.
So, the dilemma... What should Kolari adjust focus for? The current mod appears perfect with the Novoflex - at least on properly adjusted lenses. It will be interesting to run through my larger collection and see if they are all acceptable with this adapter. I'll report on that when I have time.
With the VM-E there is some room for a lens to be off and still hit infinity. With a lot of 50+ year old lenses out there and in my collection (Leica, Canon, Nikor, etc.) I imagine some might have issues on the Novoflex, so the "safety margin" on the VM-E might be welcome. And, if those lenses are off with the Novoflex (which, again, seems properly calibrated on my A7M), they are going to be off on the Leica rangefinder, too.
So... which adapter are you using? I think a survey would be valuable as we continue to develop these modifications. If people want to PM me with their adapter choices, I'll compile some info and publish he results.
Michael
Feb 07, 2015 at 07:57 PM
p.13 #10A thinner sensor stack may be possible after all!
mdemeyer wrote:
...and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses
So, the dilemma... What should Kolari adjust focus for?
I noticed that too and I feel it works well for me. See, if a precise focus at 500-->1000 --> ∞ meters is desired for landscaping shots, some degree of framing and focusing precision is required and focus EVF/LCD magnification can very precisely nail it with all lenses (all, as forget the hard stop you had with xxx camera)
...and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses
So, the dilemma... What should Kolari adjust focus for?
I noticed that too and I feel it works well for me. See, if a precise focus at 500-->1000 --> ∞ meters is desired for landscaping shots, some degree of framing and focusing precision is required and focus EVF/LCD magnification can very precisely nail it with all lenses (all, as forget the hard stop you had with xxx camera)
Feb 07, 2015 at 08:45 PM
p.13 #11A thinner sensor stack may be possible after all!
Thank you Michael for the heads up. It seems that Charlie is not having any problem with his adapter. Personally, I am using the Hawk's Factory V3 adapter right now, so I don't think the minor difference would be an issue since I can adjust infinity on this one (same thing of the Phigment adapter). I also have a Kindai (Rayqual) coming in but I can't report back until I get back my A7s.mod, which would be around mid-March 
. Right now, I'm afraid that the Kindai might not work well after the mod since Kindai adapter tends to get spot-on infinity as-is (better construction/design compared to Novoflex as well).
. Right now, I'm afraid that the Kindai might not work well after the mod since Kindai adapter tends to get spot-on infinity as-is (better construction/design compared to Novoflex as well).Feb 07, 2015 at 08:59 PM
p.13 #12A thinner sensor stack may be possible after all!
To be clear, I don't think there will be any problem after the mod.
My experience is that focus with the VM-E seems to be the same before and after. (FYI, we used the VM-E and adjusted to achieve the same before and after in developing the mod.) I presume that the same statement would be true for the Novoflex, but I didn't own it before, so can't confirm.
So, if you have something that works now, I expect it will work the same after modification.
Michael
My experience is that focus with the VM-E seems to be the same before and after. (FYI, we used the VM-E and adjusted to achieve the same before and after in developing the mod.) I presume that the same statement would be true for the Novoflex, but I didn't own it before, so can't confirm.
So, if you have something that works now, I expect it will work the same after modification.
Michael
Feb 07, 2015 at 09:08 PM
p.13 #13A thinner sensor stack may be possible after all!
mdemeyer wrote:
This test shows me that even the two most well-respected adapters don't appear to be the same. (I can't find my micrometer at the moment, but will post the measurements when I put my hands on it.) And let's not even talk about the legions of Ebay cheapies.
Michael
To complicate matters, I was told by my well known Leica repairman in Los Angeles that some M lenses can never be perfectly calibrated at infinity throughout the aperture range, which wasn't so much of an issue with film. If you want bang on infinity focus wide open, the lens may be a little off stopped down, and vice versa. In my case, it was the 35 Summicron IV that had this issue. My 35 Summicron ASPH seemed to be closer at both ends of the aperture range.
This test shows me that even the two most well-respected adapters don't appear to be the same. (I can't find my micrometer at the moment, but will post the measurements when I put my hands on it.) And let's not even talk about the legions of Ebay cheapies.
Michael
To complicate matters, I was told by my well known Leica repairman in Los Angeles that some M lenses can never be perfectly calibrated at infinity throughout the aperture range, which wasn't so much of an issue with film. If you want bang on infinity focus wide open, the lens may be a little off stopped down, and vice versa. In my case, it was the 35 Summicron IV that had this issue. My 35 Summicron ASPH seemed to be closer at both ends of the aperture range.
Feb 07, 2015 at 09:12 PM
p.13 #14A thinner sensor stack may be possible after all!
mdemeyer wrote:
In response to some earlier discussion on this thread about infinity focus on the mod, I suspect most who have alt lens experience understand that there is a dilemma when deciding on the 'proper' infinity focus adjustment. Remember, the sensor does have to be moved in the mod, since the thinner stack has a shorter optical path length.
I normally use the Voigtlander VM-E Close Focus adapter on the A7, and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses. (This is the same as the camera before the mod.)
However, for the project I...Show more →
Still awaiting my A7rM
When I first received my A7r I measured three of my Novoflex adapters with a micrometer and there were differing tolerances and in some cases I could not focus to infinity(problem) with a few of my older M lenses. There are variations even with the same make of adapters. I also found the Metabones as supplied by Sony did also have variations. The VM-E, IMO have the best overall tolerances and the best fit.
I was about to send my A7r with Novoflex and my WATE to Camera Clinic to ensure the adapter was calibrated, no different than sending my older M lenses and M9/M240 to re-calibrated. All my M lenses have been carefully calibrated and they do drift. The weight of the 50 Nocti f/1.0, 75 Lux and 90 Cron AA does place stress on the mount and after about 1 or 2 years they do need to be checked.
I intend once I have tested and picked my favourite M lenses, I will send the A7rM and select M lenses with my VM-E adapters and have to them fine tuned and calibrated. This only takes about a day and the results are definitive.
Charlie. Very nice shots! Ron's shots with the 28 Cron Asph are great, though I think Ron could make any WA lens shine
In response to some earlier discussion on this thread about infinity focus on the mod, I suspect most who have alt lens experience understand that there is a dilemma when deciding on the 'proper' infinity focus adjustment. Remember, the sensor does have to be moved in the mod, since the thinner stack has a shorter optical path length.
I normally use the Voigtlander VM-E Close Focus adapter on the A7, and with that adapter my modified A7 does go slightly past infinity on properly calibrated lenses. (This is the same as the camera before the mod.)
However, for the project I...Show more →
Still awaiting my A7rM
When I first received my A7r I measured three of my Novoflex adapters with a micrometer and there were differing tolerances and in some cases I could not focus to infinity(problem) with a few of my older M lenses. There are variations even with the same make of adapters. I also found the Metabones as supplied by Sony did also have variations. The VM-E, IMO have the best overall tolerances and the best fit. I was about to send my A7r with Novoflex and my WATE to Camera Clinic to ensure the adapter was calibrated, no different than sending my older M lenses and M9/M240 to re-calibrated. All my M lenses have been carefully calibrated and they do drift. The weight of the 50 Nocti f/1.0, 75 Lux and 90 Cron AA does place stress on the mount and after about 1 or 2 years they do need to be checked.
I intend once I have tested and picked my favourite M lenses, I will send the A7rM and select M lenses with my VM-E adapters and have to them fine tuned and calibrated. This only takes about a day and the results are definitive.
Charlie. Very nice shots! Ron's shots with the 28 Cron Asph are great, though I think Ron could make any WA lens shine
Feb 07, 2015 at 09:21 PM
p.13 #15A thinner sensor stack may be possible after all!
hiepphotog wrote:
Thank you Michael for the heads up. It seems that Charlie is not having any problem with his adapter. Personally, I am using the Hawk's Factory V3 adapter right now, so I don't think the minor difference would be an issue since I can adjust infinity on this one (same thing of the Phigment adapter). I also have a Kindai (Rayqual) coming in but I can't report back until I get back my A7s.mod, which would be around mid-March. Right now, I'm afraid that the Kindai might not work well after the mod since Kindai adapter tends to get...Show more →
Yes this is the adapter I am using. I have not adjusted it for infinity and it goes well past that. I should get off the couch and do that, since I hate focusing for infinity, and am totally spoiled by the M9. But I've never had one adapter since the Nex-5 which had infinity correct so I sort of take this PITA for granted.
I'm shooting fast quite often, and I never thought I would say this: my hit rate is way better with M9! It took a while but now I shoot WO often with fast lenses. Of course I miss with both cameras. The M9 is also faster.
I'm no newbie with A7 focus: I've shot 75K frames MF at least with one version or the other. But now that I like the camera again I will have to train myself better.
Here is the Sonnetar 50 @about 1.3 today:
DSC01095 by unoh7, on Flickr
Demonstrating that the M9 is not the only camera to vary Auto WB wildly with light source and color
Thank you Michael for the heads up. It seems that Charlie is not having any problem with his adapter. Personally, I am using the Hawk's Factory V3 adapter right now, so I don't think the minor difference would be an issue since I can adjust infinity on this one (same thing of the Phigment adapter). I also have a Kindai (Rayqual) coming in but I can't report back until I get back my A7s.mod, which would be around mid-March
. Right now, I'm afraid that the Kindai might not work well after the mod since Kindai adapter tends to get...Show more →Yes this is the adapter I am using. I have not adjusted it for infinity and it goes well past that. I should get off the couch and do that, since I hate focusing for infinity, and am totally spoiled by the M9. But I've never had one adapter since the Nex-5 which had infinity correct so I sort of take this PITA for granted.
I'm shooting fast quite often, and I never thought I would say this: my hit rate is way better with M9! It took a while but now I shoot WO often with fast lenses. Of course I miss with both cameras. The M9 is also faster.
I'm no newbie with A7 focus: I've shot 75K frames MF at least with one version or the other. But now that I like the camera again I will have to train myself better.
Here is the Sonnetar 50 @about 1.3 today:
DSC01095 by unoh7, on Flickr
Demonstrating that the M9 is not the only camera to vary Auto WB wildly with light source and color
Feb 07, 2015 at 09:55 PM
p.13 #16A thinner sensor stack may be possible after all!
Thanks for the shots with the Elmarit 28, I suspect my v2 will be improved with an A7rm, I also would expect my 24 Elmarit Asph to also be improved.
Feb 08, 2015 at 01:34 AM
p.13 #17A thinner sensor stack may be possible after all!
douglasf13 wrote:
MichaelTo complicate matters, I was told by my well known Leica repairman in Los Angeles that some M lenses can never be perfectly calibrated at infinity throughout the aperture range, which wasn't so much of an issue with film. If you want bang on infinity focus wide open, the lens may be a little off stopped down, and vice versa. In my case, it was the 35 Summicron IV that had this issue. My 35 Summicron ASPH seemed to be closer at both ends of the aperture range.
Quirks abound, but I'm surprised how well the infinity stops works on nearly all my M and LTM glass in the situations where I really want it. That's usually stopped down, for sure.
When I made some threads about the 75 lux at MF lenses I heard all kinds of nightmare stories with bad cams, apparently also an issue in some Canandian 90 crons.
But if a quirky lens is used often pretty soon the shooter start to learn it , and pull back a tad or roll out to infinity x amount. I just walk around my yard and chimp to learn my off lenses. Works pretty decent and the "english" stays in your memory if you use the lens. My 135 APO front focuses just a tad: always.
mdemeyer wrote
This test shows me that even the two most well-respected adapters don't appear to be the same. (I can't find my micrometer at the moment, but will post the measurements when I put my hands on it.) And let's not even talk about the legions of Ebay cheapies.Michael
Quirks abound, but I'm surprised how well the infinity stops works on nearly all my M and LTM glass in the situations where I really want it. That's usually stopped down, for sure.
When I made some threads about the 75 lux at MF lenses I heard all kinds of nightmare stories with bad cams, apparently also an issue in some Canandian 90 crons.
But if a quirky lens is used often pretty soon the shooter start to learn it , and pull back a tad or roll out to infinity x amount. I just walk around my yard and chimp to learn my off lenses. Works pretty decent and the "english" stays in your memory if you use the lens. My 135 APO front focuses just a tad: always.
Feb 08, 2015 at 01:45 AM
p.13 #18A thinner sensor stack may be possible after all!
Douglas, if a lens cannot be calibrated at both ends, it should be sent to Leica, who can reshape the cam.
Feb 08, 2015 at 03:19 AM
p.13 #19A thinner sensor stack may be possible after all!
Reverting to the topic of the former page about bets, I'll make my own based purely on non optical reasoning.
Yes, it seems that if we modify the design of a film era lens ( i.e. Biogon ZM35/2) to perform it's best with a specified glass cover in mind, the resulting lens (Loxia 35) should be as good as the original glass on film -or in a digital camera with a extremely thin cover.
What happens when we translate a page of text from English to another language and the resulting text is translated back to English?. In theory we should get exactly the same original phrases. Experience tell us that this is not true, There's always something lost in the way every time we translate.
I have the strong hunch that the same happens in optics. Yes, in theory it's possible to counteract the additional astigmatism and field curvature induced by a sensor cover, with a negative astigmatism and FC. in order to preserve exactly the original performance of the lens. In the real world though, I suspect that perfection in optics isn't possible and something is always lost in that double interaction.
Therefore, my bet ( make it $0.99 at most ) :
The best Biogon on a Leica M ( or anything with a super thin cover glass) will always be somehow better than the best Loxia on a Sony A7x with a thick cover, no matter how Zeiss tries hard.
Yes, it seems that if we modify the design of a film era lens ( i.e. Biogon ZM35/2) to perform it's best with a specified glass cover in mind, the resulting lens (Loxia 35) should be as good as the original glass on film -or in a digital camera with a extremely thin cover.
What happens when we translate a page of text from English to another language and the resulting text is translated back to English?. In theory we should get exactly the same original phrases. Experience tell us that this is not true, There's always something lost in the way every time we translate.
I have the strong hunch that the same happens in optics. Yes, in theory it's possible to counteract the additional astigmatism and field curvature induced by a sensor cover, with a negative astigmatism and FC. in order to preserve exactly the original performance of the lens. In the real world though, I suspect that perfection in optics isn't possible and something is always lost in that double interaction.
Therefore, my bet ( make it $0.99 at most ) :
The best Biogon on a Leica M ( or anything with a super thin cover glass) will always be somehow better than the best Loxia on a Sony A7x with a thick cover, no matter how Zeiss tries hard.
Feb 08, 2015 at 04:39 AM
p.13 #20A thinner sensor stack may be possible after all!
carstenw wrote:
Douglas, if a lens cannot be calibrated at both ends, it should be sent to Leica, who can reshape the cam.
Perhaps I'm not following but I thought Douglas was referring to focus shift, which is a real issue with a number of classic rangefinder lenses. Are you suggesting there is some sort of calibration of the rangefinder that somehow adjusts for focus shift at different apertures?
Douglas, if a lens cannot be calibrated at both ends, it should be sent to Leica, who can reshape the cam.
Perhaps I'm not following but I thought Douglas was referring to focus shift, which is a real issue with a number of classic rangefinder lenses. Are you suggesting there is some sort of calibration of the rangefinder that somehow adjusts for focus shift at different apertures?
Feb 08, 2015 at 09:50 AM