Carl Gruber wrote:
Thank you for all your input on this. Indeed I have been looking for a number of years for the “perfect” digital G2 body. I’m already invested in the Sony E lens (a6000) and Canon EF lens (5DmkII) systems, so adding yet another (Nikon Z6) wouldn’t be optimal. Is there something about the Nikon Z6 that makes it better with the Contax G lens system than the Sony or a Canon system?
Personally, the Techartpro TZG adapter on the Z6 was a great win for me and a PCX on the wide angle CGs is pretty decent compared to Sony examples from the past. Have no Canon knowledge unfortunately.
I just had my Sony A7RII modified by Kolari (thin filter) So far I have tested:
Voigtlander 40mm classic: corners/midframe are marginally better, but still soft. This lens suffers from massive inward field curvature and focus shift. If you focus the center of the frame to infinity the corners are focused much closer. If you focus for the corners, the center is very soft. It requires at least F11 to get somewhat even sharpness across the frame. Kolari mod didn't help much. I can still recommend this lens if you like it's character/bokeh and don't care about sharpness.
Snapshot Skopar 25mm: small improvement. Corners might be a bit sharper than before but still takes F11 to get even across the frame sharpness. Cool little lens with very nice rendering.
Color Skopar 35mm F2.5 same as above, not much (if any) improvement. Cool lens with nice rendering/colors, lots of microncontrast in the center frame, and funky bokeh, but not if you need sharp corners.
Ultron 35mm F2: Looks about the same or maybe worse than before. This lens was pretty much perfect at F8/infinity before, now I'm noticing the corners are a tiny bit soft. Btw, this lens is a best kept secret. It performs beautifully.
Ultron 28 F2 V2: Looks about the same (i.e. needs F8). This is also a great lens on a stock Sony, but it does require smaller apertures (5.6/8) to get the corners sharp. It is also very well corrected (LoCA/LaCA).
Color Skopar 21mm F3.5: Looks about the same (ok at all apertures)/
I still have to do more testing, but so far the Kolari thin filter mod is not to my linking.
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With regards to the Contax G lenses:
The 21mm Biogon: Is supposed to perform great with a PCX filter on a stock Sony. I have not tested it myself.
The 28mm Biogon: I haven't tested this lens yet on the modded RII, but I have tested it with the PCX filter on a regular Sony A7RIII and it's very sharp across the frame at F8 with lots of microcontrast from F2.8-F5.6. This lens vignettes a lot (but that is true of all Biogon lenses), and there is a small amount of color shift in the corners/edges. I think it's a good lens with good performance and character.
The 35mm F2: Center is sharp at all apertures, but it's a smeary mess from the midframe to the corners on a regular Sony A7RII/III. Not recommended.
The 45mm Planar: Excellent in the center from F2, but requires f5.6/F8 for midframe and corners to get sharp. Some vignetting. Good lens/performance on a stock Sony. Great microcontrast, ok character/bokeh, colors are good.
The 90mm: No issues on stock Sony. It's an ok performer, with some LoCA at F2.8.
I am very interested in the Kolari mod too, but I still did not do it. Is the performance of those lenses worser, or comparable, than in a Leica-m?
Thanks!
m43hero wrote:
I just had my Sony A7RII modified by Kolari (thin filter) So far I have tested:
Voigtlander 40mm classic: corners/midframe are marginally better, but still soft. This lens suffers from massive inward field curvature and focus shift. If you focus the center of the frame to infinity the corners are focused much closer. If you focus for the corners, the center is very soft. It requires at least F11 to get somewhat even sharpness across the frame. Kolari mod didn't help much. I can still recommend this lens if you like it's character/bokeh and don't care about sharpness.
Snapshot Skopar 25mm: small improvement. Corners might be a bit sharper than before but still takes F11 to get even across the frame sharpness. Cool little lens with very nice rendering.
Color Skopar 35mm F2.5 same as above, not much (if any) improvement. Cool lens with nice rendering/colors, lots of microncontrast in the center frame, and funky bokeh, but not if you need sharp corners.
Ultron 35mm F2: Looks about the same or maybe worse than before. This lens was pretty much perfect at F8/infinity before, now I'm noticing the corners are a tiny bit soft. Btw, this lens is a best kept secret. It performs beautifully.
Ultron 28 F2 V2: Looks about the same (i.e. needs F8). This is also a great lens on a stock Sony, but it does require smaller apertures (5.6/8) to get the corners sharp. It is also very well corrected (LoCA/LaCA).
Color Skopar 21mm F3.5: Looks about the same (ok at all apertures)/
I still have to do more testing, but so far the Kolari thin filter mod is not to my linking.
-----
With regards to the Contax G lenses:
The 21mm Biogon: Is supposed to perform great with a PCX filter on a stock Sony. I have not tested it myself.
The 28mm Biogon: I haven't tested this lens yet on the modded RII, but I have tested it with the PCX filter on a regular Sony A7RIII and it's very sharp across the frame at F8 with lots of microcontrast from F2.8-F5.6. This lens vignettes a lot (but that is true of all Biogon lenses), and there is a small amount of color shift in the corners/edges. I think it's a good lens with good performance and character.
The 35mm F2: Center is sharp at all apertures, but it's a smeary mess from the midframe to the corners on a regular Sony A7RII/III. Not recommended.
The 45mm Planar: Excellent in the center from F2, but requires f5.6/F8 for midframe and corners to get sharp. Some vignetting. Good lens/performance on a stock Sony. Great microcontrast, ok character/bokeh, colors are good.
The 90mm: No issues on stock Sony. It's an ok performer, with some LoCA at F2.8.
I don't own a Leica M, but from my research I would say an M10/R or M11 will look better, as those cameras have other optimizations than just a thin sensor glass/filter (angled microlenses, copper wiring, built-in lens profiles).
Btw, the other issue I forgot to mention about the Kolari mod is that it messes up the white balance, sometimes requiring post editing in software as the camera's range is not enough to compensate. This is well documented in the forums and Kolari website, still it's worth noting.
hanay78 wrote:
Hi,
I am very interested in the Kolari mod too, but I still did not do it. Is the performance of those lenses worser, or comparable, than in a Leica-m?
m43hero wrote:
Color Skopar 35mm F2.5 same as above, not much (if any) improvement. Cool lens with nice rendering/colors, lots of microncontrast in the center frame, and funky bokeh, but not if you need sharp corners.
Just some comments on the Color Skopar 35mm F2.5, a real favorite of mine.
The lens has noticeable field curvature even on film.
But on a OEM sensor stack, you can't have the center in focus and the corners in focus at the same time at any aperture and the corners never get very good at all.
On a thin sensor stack (I have an A7rII, NKIR modded camera, which is thinner than Kolari), the curvature is much better, but still exists. Wide open, you can get decent corners if you focus on them, but the center gets a quite soft. At f/5.6, if you focus on the center, the corners are fine, but not great, but if you focus on the corners, you get excellent sharpness across the frame.
I have the lens too, and i will not sell it, I really adore the size and the performance with the sun in the frame, but in a stock camera is quite unusable. Your observations mean one must use f8 for good performance, even in a thin sensor camera... Anybody use the lens in a m10, m11 ?
MAubrey wrote:
Just some comments on the Color Skopar 35mm F2.5, a real favorite of mine.
The lens has noticeable field curvature even on film.
But on a OEM sensor stack, you can't have the center in focus and the corners in focus at the same time at any aperture and the corners never get very good at all.
On a thin sensor stack (I have an A7rII, NKIR modded camera, which is thinner than Kolari), the curvature is much better, but still exists. Wide open, you can get decent corners if you focus on them, but the center gets a quite soft. At f/5.6, if you focus on the center, the corners are fine, but not great, but if you focus on the corners, you get excellent sharpness across the frame....Show more →
hanay78 wrote:
I have the lens too, and i will not sell it, I really adore the size and the performance with the sun in the frame, but in a stock camera is quite unusable. Your observations mean one must use f8 for good performance, even in a thin sensor camera... Anybody use the lens in a m10, m11 ?
Yeah f/8 is safe. But I still use f/5.6 if I'm shooting landscape have the time luxury of checking focus or am on a tripod.
I owned a modified version in L39 mount (Avenon).
For this old design lenses, the induced curvature on sensor is real. I could use it only on m10 body and it was better than any pre aspherical 28mm elmarit, ( Elmarit 11804 show field curvature even on m10).
45 and 90 are fine.
My suggestion is buy a simple mecanical adapter, do not modify G lenses but send them to a service for cleaning/lubing, keep the 28mm for film, without cutting internal shader, there are a lot of choice that work a lot better on digital in 24/28mm with a fair price.
For the body, follow your taste and your wallet.
Any thoughts on the Contax G 28mm MS Optics modded for Leica M? I have an M10 and would love to know if this combo is any good. Theyre pretty pricy so thoughts on them vs the VM and ZM offerings would be appreciated!
EDIT: wanted to add that I use the CG45 on an NEX-5n many years ago and I really enjoyed that combo.
If I were buying a 28/2.8 lens for a rangefinder camera today I'd probably go with the VM 28/2.8 Color-Skopar that was released last year. I'd only consider the Contax if I preferred its rendering/character, because the Voigtländer has a lot going for it and will be easier to use on Leica as well as adapted to Sony and other mirrorless cameras.
Carl Gruber wrote:
I have a Contax G2 with the G28, G45 and G90 lenses.Years ago I bought an inexpensive Fotodiox adapter and tried them out on my Sony a6000.. The results were ok, but the G28 had a lot of chromatic aberration and the corners were completely blurry. I understand that is common for RF lenses on digital.
My question is, have things improved in 2023? I”m thinking of buying either the a6700 or the a7cII. I’d prefer to not have the crop factor, so I’m leaning towards the a7cII if the corners are sharp with minimal chromatic aberration. I’m not willing to modify the lenses as I still would like to be able to shoot with my Contax G2. I’m not wed to Sony, so if there are better alternatives, I’m open to Canon or others.
Thanks for any advice on the state of Contax G lenses on digital in 2023....Show more →
My fairly recent tests with the G 28 adapted to the Leica SL2 ( perhaps the thinnest FF digital mirrorless sensor stack of them all) IMO the Contax G 28 still needs a PCX filter and even then much better but not optimal. One of these days I keep telling myself I'll buy a G2 and give my Contax G lenses what they deserve.
I have a Contax 45mm just sitting around collecting dust. Previously, I bought a bulky manual focus adapter for it to put on my A7, but never liked the experience and weight of it.
I now have an A7 and a Zf. What are the adapter options these days? I see Techart makes an AF adapter, which is probably the best experience, but what about the manual focus adapters? Urth makes one (for Sony) that seems way smaller than the one I have, but I'm not sure how smooth the manual focusing would be on it: https://urth.co/products/contax-g-lens-mount-to-sony-e-camera-mount
Anyone still using Contax G lenses on their Sony / Nikon?
BastianK wrote:
Have a look at my Hologon review that I posted already.
Or have a look at my VM 15mm 4.5 II review.
All these lenses are awful on M9/M240 because their sensors are awful.
On M10 vignetting is significantly reduced but you get asymmetrical color cast (that can be fixed in post, how to do that I also described).
Use a Sony Gen2+ camera or a Leica M11 (that also uses a Sony sensor) and that color cast is almost gone.
The thick filter stack of the Sony cameras will ruin the corner sharpness,
to also fix that you can modify the camera with a thinner filter stack.
As said, have a look at the Hologon review, the information with a bunch of comparisons is all there.
And the Hologon is the absolute worst lens in that regard, the ZMs have mild issues at worst by comparison.
Not on an M9/M240 though, here they are all awful. ...Show more →
I realise that this discussion is over a year old, I just happened to see it when a post earlier today caused the thread to reappear.
You are, I think, quite correct about using the ZM 21/4.5 on the M11. I have tried it myself, it seems more than good enough to me. And a thread on the Leica forum confirms it, here. My understanding is that it is also quite correct to say that the color shift was noticeably bad on earlier M digital cameras.
weezintrumpete wrote:
I have a Contax 45mm just sitting around collecting dust. Previously, I bought a bulky manual focus adapter for it to put on my A7, but never liked the experience and weight of it.
I now have an A7 and a Zf. What are the adapter options these days? I see Techart makes an AF adapter, which is probably the best experience, but what about the manual focus adapters? Urth makes one (for Sony) that seems way smaller than the one I have, but I'm not sure how smooth the manual focusing would be on it: https://urth.co/products/contax-g-lens-mount-to-sony-e-camera-mount
Anyone still using Contax G lenses on their Sony / Nikon? ...Show more →
Don't know if the adapters have gotten better, but I still shoot my converted contax g on my a7c and kolari a7. More the g21, 28, and 35 than the 45 though.
sebboh wrote:
Don't know if the adapters have gotten better, but I still shoot my converted contax g on my a7c and kolari a7. More the g21, 28, and 35 than the 45 though.
What conversion kit did you use, or who did it? I like the Contax 45mm and would consider converting it depending on cost.
Reviving this thread.
Have been trying out the new shoten GTZ (AF)adapter on the Nikon ZF & experience has been promising!
The new adapter is ages ahead from past adapters in terms of AF speed, Exif recording, af mode support. The CG 90 lens that suffered hunting & froze on every Techart AF adapter in the past has been without issue here. AF Compatible & safe with all CG lenses including the Hologon! Manual focus wheel takes a little getting used to but is a breeze once acquainted.
Special mention must be made of the manual focus override and Macro focus mode via the adapter control that transforms the usability and decreases min focus distance .
I have a G1 and 21/28/45/90, I still use my G as sometimes it is useful to have a film point and shoot especially if the camera is to be handed someone else that would find manual anything too much of a challenge. I have adapted all to Nikons and all work but infinity for the 45 seems to come up just a hair short with all the adapters. I bought a fun leader adaption of the 45/2 for my M and that I use. Probably not cost efficient compared to buying Cosina or TT lens and almost new Zeiss cost. But I like the 45/2 and so I did and use it. It is a good size balance for a MP or M11, although my intent was more MP so to be Leica with the 45/2 film rather than G. If I was to get another adapted it would probably be a 21mm the Contax lens is good from both weight and size perspective if redone as M. There are a number of adaptions at various price points, probably none make economic sense compared to buying different lens, but if you really like a lens like I do for the 45/2 (it is awesome at F5.6-8) then that is the reason. You can still get 21, 28, 45 adaptions "new" (old glass maybe NOS), and there are others floating around on eBay from ms-optics and others used with the usual caveats about purchase.
The new Cosina line of M APOs will cost no more than adaptation..... I am increasingly thinking of moving on and use my G as a G with the exception of the 45/2 M that I already have.
I just got the Contax Zeiss 28mm 2.8 and adapted it to the Nikon Z50 (APS-C). I really like the results. As far as I can tell, corners etc. are all good. Way better (sharpness, contrast, vibrancy) than the Nikkor DX 24mm 1.7. Manual focusing is a bit cumbersome, though.
I will post some example shots the next days.
Once I used the 45mm f2 on a Sony NEX and loved the results as well. Maybe the corner issues are more likely to appear on FF?
