A7M: help with RF wide performance

Here is shot with ZM 18

DSC00220 by unoh7, on Flickr

I will get you all better ones with ZM18 SEM 21 and 28cron within a week.

Colorcast is still there for sure but smearing is way way down.
 
Wow, this is a lovely option. So many industrious and capable people in the world today. What a treat for photographers.

Quick question: what will this do to FE wide angle lenses? and just any DSLR style lenses? Will it affect them at all?
 
Thanks, Charlie, for the update. Look forward to seeing more!

The improvement is remarkable.

It's been fun to follow the excitement here and over at FM about this.

Since I travel in humid places and don't live in North America, I'm waiting for Kolarivision to come up with a new glass that will be corrosion-proof or corrosion-resistant. (Anyway, my ZI is coming back from Oberkochen soon, so I've got plenty to keep myself occupied!).
 
Thanks Charlie - you wouldn't happen to have a ZM 25/2.8 Biogon that you can test, do you? That is one of my favorite lenses, but it fails miserably on my A7R. If the mod shows the same level of improvement as it did for the ZM 18mm (thanks by the way), I'm sold.
 
kxl said:
Thanks Charlie - you wouldn't happen to have a ZM 25/2.8 Biogon that you can test, do you? That is one of my favorite lenses, but it fails miserably on my A7R. If the mod shows the same level of improvement as it did for the ZM 18mm (thanks by the way), I'm sold.
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sry do not have the 2.8 but here is the ZM35/2 which was also bad.


DSC00304 by unoh7, on Flickr


DSC00306 by unoh7, on Flickr

these at f/5.6

I think we are seeing a big improvement, but the M240 is still a bit better on the edges, I'd guess, but suddenly the camera is quite decent with these two lenses. Had it been this good stock I doubt I would have bought an M9. I love that camera and am glad I have it now.

AF seems to work fine with sony lenses as well.

Minimal PP on all these.
 
Does anyone know what this mod will do to standard FE wide-angle lenses? What will it do to dslr-style, telecentric designs (probably nothing I'd assume).
 
Samouraï said:
Does anyone know what this mod will do to standard FE wide-angle lenses? What will it do to dslr-style, telecentric designs (probably nothing I'd assume).
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Probably nothing. These lenses are designed to be used on a variety of cover glass thicknesses (the NEX cameras had thinner covering). My guess is that the glass wasn't even taken into consideration, or it may be part of the default correction process (i.e. cropping out the bad corners).

Most DSLR lenses are also not designed with covering in mind, since their flange distance is long enough to ignore minor glass thickness differences.

I have some assignments coming up but I will be sending either an A7 or one A7 plus one A7S in for the results.
 
Samouraï said:
Does anyone know what this mod will do to standard FE wide-angle lenses? What will it do to dslr-style, telecentric designs (probably nothing I'd assume).
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The FE35 and 55 will be a little less good on a mod body, according to tests with the mod at lens rentals.These lenses were specifically designed for the thick CG.

The new zeiss 35/2 loxia may be better. Most SLR glass should be better. Any lens designed for film should be better.

Since the A7 could not shoot canon AF glass as well as a 5D, I would think alot of newer non-FE glass should do better.

These differences will become more subtle as the film lenses get longer, but they should still show up on a close look.

Apparently the Lux ASPH 50 is way better 🙂
 
uhoh7 said:
The FE35 and 55 will be a little less good on a mod body, according to tests with the mod at lens rentals.These lenses were specifically designed for the thick CG.

The new zeiss 35/2 loxia may be better. Most SLR glass should be better. Any lens designed for film should be better.

Since the A7 could not shoot canon AF glass as well as a 5D, I would think alot of newer non-FE glass should do better.

These differences will become more subtle as the film lenses get longer, but they should still show up on a close look.

Apparently the Lux ASPH 50 is way better 🙂
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Very very interesting. I suppose they went with a thicker sensor glass for durability? I hope the thinner glass isn't a liability, though I suppose nothing should ever touch it, ideally.
 
Samouraï said:
Very very interesting. I suppose they went with a thicker sensor glass for durability? I hope the thinner glass isn't a liability, though I suppose nothing should ever touch it, ideally.
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It may do the M9 corrosion thing, but they say they will stand behind it.

We cannot say anything about the long run. But I feel a camera I rarely use has been resurrected. 🙂

A7m + sonnetar @ f/1.1:

Blue Wall by unoh7, on Flickr
 
Wow!

Wow!

I'm surprised there hasn't been much more excitement here about this modification.

I'm really excited. I definitely want a modified A7s, such a great complement to my ZI and R4A with film.

Too bad I don't have the money.

Nothing else in the digital realm as a body for my M lenses excites me as much as this.
 
uhoh7 said:
The FE35 and 55 will be a little less good on a mod body, according to tests with the mod at lens rentals.These lenses were specifically designed for the thick CG.
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This would be a concern for me, and even more so if the same is true for the yet to be released FE 28/2.0. The 55/1.8 is one of, if not the best lens for the FE platform, and to make it even a 'little less good' is not acceptable.

I'm not willing to sacrifice FE lens performance to make adapted M-mount lenses more usable. So, if the mod truly will adversely impact FE lenses, I may pass on this mod.
 
Based on the tests done at lensrentals, the sacrifice is virtually insignificant, and surely indiscernible.

So far, the ONLY downside appears to be the vulnerability to corrosion (of sensor cover glass) as early as one year after conversion. To their credit, Kolarivision are totally upfront about this, and informally offer a perpetual conversion.

Naturally, other risks are inevitably involved when one engages a third-party modification upon the imaging sensor.

If I lived in North America, I wouldn't be too worried about these risks and costs.
 
Samouraï said:
Does anyone know what this mod will do to standard FE wide-angle lenses? What will it do to dslr-style, telecentric designs (probably nothing I'd assume).
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One way of thinking is that the cover-glass is an imperfection and that thinning it or removing it will improve things in all cases. I don't think that's a good model.

A different way of thinking of this is that a modern lens of quality is designed for a specific glass thickness. Changing that cover glass may well de-optimize the design.

See this post, from the series by Roger Cicala at LensRentals. It shows that a Zeiss Otus plus a new Brian Caldwell SpeedBooster with excellent pedigree, designed for a specific cover glass thickness, turns into a very ordinary lens when the cover glass is not present. The difference is dramatic.

One key quote from the article: "Lens designers plan for the thickness of the sensor stack..."

Lenses designed for no-glass get better when the glass is thinner. The A7 with this mod may well be a great solution for shooting with M lenses.

I expect lenses designed for a glass in the path get worse if that glass is removed. I would hesitate to try to out-think the Sony/Zeiss engineers.

Maybe one needs a dedicated body for excellent results with RF wides.
 
noimmunity said:
Based on the tests done at lensrentals, the sacrifice is virtually insignificant, and surely indiscernible.
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From the lensrental.com blog:

"I should also point out that there is a slight decrease in corner resolution with the modified camera compared to stock. A difference of 20 lp/IH is almost certainly not significant. The difference of 40 lp/IH might be, that's about the range where we see a consistent difference."

If I understand it correctly, their test shows a difference of 40 lp/IH wrt corner resolution for the FE 55/1.8, which, in their own words, "might be" significant.

I should point out that I shoot quite a bit of landscape images with the A7R and FE 55/1.8 and do make large prints (including metal prints) and for those types of images, corner resolution is important. If I were using this for people or street photos, then I'd be all over this mod.

Granted, they only refer to this as a small sample test, and not intended to be definitive, but it is enough to give me pause. I'm usually a later adopter of new technology anyway, so I will most likely wait for more definitive tests before I buy into this mod.
 
kxl said:
From the lensrental.com blog:

"I should also point out that there is a slight decrease in corner resolution with the modified camera compared to stock. A difference of 20 lp/IH is almost certainly not significant. The difference of 40 lp/IH might be, that's about the range where we see a consistent difference."

If I understand it correctly, their test shows a difference of 40 lp/IH wrt corner resolution for the FE 55/1.8, which, in their own words, "might be" significant.

I should point out that I shoot quite a bit of landscape images with the A7R and FE 55/1.8 and do make large prints (including metal prints) and for those types of images, corner resolution is important. If I were using this for people or street photos, then I'd be all over this mod.

Granted, they only refer to this as a small sample test, and not intended to be definitive, but it is enough to give me pause. I'm usually a later adopter of new technology anyway, so I will most likely wait for more definitive tests before I buy into this mod.
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I have two A7's. I'll send in one and keep the other for native/A-mount lenses. With used A7 bodies consistently going at ~$900, I think a second body might not be a bad idea?

For me the question is whether I should send in the A7S...I use it for low light, mostly when I can't see what's in the corners anyways. But it would be nice to make it AA-less.
 
YYV_146 said:
I have two A7's. I'll send in one and keep the other for native/A-mount lenses. With used A7 bodies consistently going at ~$900, I think a second body might not be a bad idea?

For me the question is whether I should send in the A7S...I use it for low light, mostly when I can't see what's in the corners anyways. But it would be nice to make it AA-less.
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Agreed. If I have two bodies, I'd certainly send one in for the mod. Whether it's worth $1300 ($900 body plus $400 mod) to buy an A7 and get this mod? Sure, if I don't have other higher-priority needs (e.g., DSLR lens >200mm).
 
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