Contax 645 Zeiss lenses on Nikon DSLR... impressive results (the JAS adapter).

[Theodoros]

The JAS adapter (850 USD cost), arrived 3 days ago so that I can now mount my 7 Contax  lenses (all but the 350mm) on my 36 & 16mp FF Nikon cameras with full aperture dedication and AF compatibility!  The adapter was purchased in order to considerably decrease the size of equipment I have to carry when both MF & DSLR is needed... Up to now I have come up with the following conclusions:

1. All the lenses have enough resolution to cope with the 36mp sensor's pixel size even at wide open aperture...
2. The famous contrast, flare resistance, colour saturation and bokeh of Zeiss, is in a class of its own if compared with Nikon glass.
3. AF performance is very good (much better than C645) on the Nikon... you do loose your DOF preview button though.
4. AF accuracy seems fine right out of the box... (although it hasn't been examined thoroughly yet).
5. JAS adapter is well made but tolerances need to be even tighter when considering the price... The lenses are easy to fit and lock securely, but (for my taste) there is some slight "wobbling" when they are locked in the bayonet... (can't affect lens performance as the movement plane is parallel to the focal plane). There is also some "idea" of tolerance (maybe a 20th of a mm) between the mount and lens... (can't be felt when shooting - only if one forces the lens to bend against the mount).  OTOH, Nikon side mount of the adapter, performs just like if it was a Nikkor lens.

 To make a long story short, I decided to sell all my Nikkor lenses but the 17-35mm f2.8, the old 35-70mm f2.8 & the 85mm F2.8 PC micro and replace the rest with the Contax glass.

I had in mind to buy a Cmos Leica S007 with Contax adapter to do the same (use my Contax glass on it) and only add the 24mm Leica lens while selling all my Nikon gear at the same time, but since then, I also bought a Sinarback 54H alongside the Imacon 528c I was using on my Contax... I then thought "why use two 16x able backs?" and decided to replace the Imacon 528c with a Hasselblad 39MS back (just after service and IR filter replaced). Since I was planning to use the S007 as single-shot MFDB with additional low light capabilities, the plan was changed into using the CF-39MS on Contax for single shot and keep low light capabilities with Nikon. A large amount of money was saved too...

[lowep]

Thanks for posting this Theodorus that is good to know. Also looks like it works fine with Canon too at least according to this user review

[Theodoros]

Hi, thanks for the link (I was unaware of it). By coincidence he first tried the same lenses first as I did, which is explainable as teles would be the most demanding ones for focus accuracy... I also added the 210/4 and then both the 140/2.8 and 210/4 with the mutar 1.4x added on... No focus inaccuracy observed either even at (almost) 300/5.6....

I'm surprised he doesn't comment on lenses performance, the result is clearly better (even with the TC added on) than the Nikkor lenses I used to use... Maybe less so for resolution (my Nikkors where no slouch), but again the rest of the performance (more important than res IMO) is clearly better with the Zeiss glass.

DR has improved considerably too... I don't mean the captured DR, but rather the DR you are left with after processing... this must be because of the higher contrast that the Zeiss lenses exhibit... Less contrast is needed with processing and thus more DR is retained... Another thing is that with the Zeiss, (all of them) one can point the camera towards the sun and flare resistance is such, that can watch the sun through the VF easily and actually capture the perimeter of the ultimate light source in real! ...Honest! ...that impressive!

I only have some (personal - maybe I'm too demanding) complains about the tolerances on the Zeiss mount side... Clearly I'm not going back on using Nikkor glass on my FF cameras. They are now a step further close to MF performance... More "filmish" than ever and with higher resolution than film. Clearly Impressed!

[Jan K.]

Thanks for the "mini review"! 

But this made me lift an eyebrow...

... I decided to sell all my Nikkor lenses but the 17-35mm f2.8, the old 35-70mm f2.8...

May I ask, why not these two?

[peterv]

Thanks for sharing Theodoros, sounds like a good option for C645 glass owners. Please show us some examples!

I wish someone would make such an adapter for my Leica S lenses.

[Theodoros]

Thanks for the "mini review"! 

But this made me lift an eyebrow...

May I ask, why not these two?

One to have for ultra WA on Nikon (because 35mm is the widest C645 available) and the other (the 35-70) because it is cheap to sell, great in performance, fast aperture and compact enough to have as a walk around lens.

[Theodoros]

Thanks for sharing Theodoros, sounds like a good option for C645 glass owners. Please show us some examples!

I wish someone would make such an adapter for my Leica S lenses.

I believe that Steel is working on this... (don't know if leaf shutter will work though - not that I would care with flash sync up to 1/250). But again, if one goes for the new S007, or doesn't need or use higher ISO with one of the older S-series, why use a DSLR at all? ...I find the Leica compact and flexible  enough... 

[lowep]

I would like to see a Sony A-mount version to couple my Contax 645 lenses to a body with in body stabilization, even though these days the future of the Sony A-mount seems to be blowing in the wind, so it may not be worth investing time and money in R&D required to do this. These days the pundits seem more excited about the E-mount... but given Sony´s mercurial track record that may not last much longer than the A-mount did?

[ErikKaffehr]

Hi,

The A-mount was introduced 1985 and the E-mount 2011.

The Canon EOS mount was introduced after the A-mount.

Canon has two different EOS mounts, full frame and APS-C. Really same with Nikon.

Canon has also the EOS-M mount, introduced in 2012.

So, I don't see Sony more mercurial than Canon.…

That said, there are reasons that Canon is number one and Sony distant third in interchangeable lens cameras.

Best regards
Erik

I would like to see a Sony A-mount version to couple my Contax 645 lenses to a body with in body stabilization, even though these days the future of the Sony A-mount seems to be blowing in the wind, so it may not be worth investing time and money in R&D required to do this. These days the pundits seem more excited about the E-mount... but given Sony´s mercurial track record that may not last much longer than the A-mount did?

[araucaria]

Canon has two different EOS mounts, full frame and APS-C. Really same with Nikon.

Nikon has the F mount, just some lenses don't cover FX and the oldest ones need some filing or the nikon df, but the mount is the same.

[Theodoros]

I would like to see a Sony A-mount version to couple my Contax 645 lenses to a body with in body stabilization, even though these days the future of the Sony A-mount seems to be blowing in the wind, so it may not be worth investing time and money in R&D required to do this. These days the pundits seem more excited about the E-mount... but given Sony´s mercurial track record that may not last much longer than the A-mount did?

Actually I don't see why making an adapter for Sony Alpha would be a problem for Steel... With such an adapter one could then add the Sony Alpha to Sony-E adapter and have all functions on both cameras... Why don't you mail Steel and ask him? I believe that Sony Alpha CPU contacts and logic are very similar to Canon Eos (which are very similar to Contax-N) and thus, there could be an easier than making the Nikon adapter task... Here is Steel's mail: steelchn@gmail.com he is also a member in Lula.

[lowep]

Hi,

The A-mount was introduced 1985 and the E-mount 2011.

The Canon EOS mount was introduced after the A-mount.

Canon has two different EOS mounts, full frame and APS-C. Really same with Nikon.

Canon has also the EOS-M mount, introduced in 2012.

So, I don't see Sony more mercurial than Canon.…

That said, there are reasons that Canon is number one and Sony distant third in interchangeable lens cameras.

Best regards
Erik

Good to know... in this case the e-mount may outlive many of us 

[lowep]

Actually I don't see why making an adapter for Sony Alpha would be a problem for Steel... With such an adapter one could then add the Sony Alpha to Sony-E adapter and have all functions on both cameras... Why don't you mail Steel and ask him? I believe that Sony Alpha CPU contacts and logic are very similar to Canon Eos (which are very similar to Contax-N) and thus, there could be an easier than making the Nikon adapter task... Here is Steel's mail: steelchn@gmail.com he is also a member in Lula.

Thanks Theodoros, if this is the case then maybe better to wait and see if Steel comes up with an E-adapter rather than requiring the piggyback solution you mention, and also if Sony comes up with a Nex 7II with image stabilization that could be a good sidekick for the larger Contax 645.

Being able to use Contax 645 lenses on the A7II that seems to be getting good reviews particularly for the image stabilization system could also be fun to try though maybe a bit big and heavy to carry around together with the Contax 645 system.

[ErikKaffehr]

Hi,

Same with Sony, both A- and E-mounts can take both FF and APS-C lenses. But Sony is called mercurial and Nikon not.

That said, Nikon has kept the F mount mechanically the same since Nikon F. I would agree that is a very good thing.

Best regards
Erik

Nikon has the F mount, just some lenses don't cover FX and the oldest ones need some filing or the nikon df, but the mount is the same.

[Theodoros]

Thanks Theodoros, if this is the case then maybe better to wait and see if Steel comes up with an E-adapter rather than requiring the piggyback solution you mention, and also if Sony comes up with a Nex 7II with image stabilization that could be a good sidekick for the larger Contax 645.

Being able to use Contax 645 lenses on the A7II that seems to be getting good reviews particularly for the image stabilization system could also be fun to try though maybe a bit big and heavy to carry around together with the Contax 645 system.

Making an adapter for C645 lenses to work on Sony Alpha with full dedication will provide a second option for one to use them on Sony-E mount (again with full dedication) since this option is already available through the C645 to EOS JAS adapter. One can add the JAS adapter for C645 lenses to work on EOS and then add the Metabones one for EOS to work on Sony E-mount.

[araucaria]

I would love to see some raw samples, theodoros

[Theodoros]

I would love to see some raw samples, theodoros

You'll have to wait... (I'll sent some whenever I have time for decent ones) Nikon is not my first priority system (C645 & Fuji GX680 with my MFDBs are....) and my posts here, have been decreased considerably due to projects running (as you may have noticed)... This post is purely informative on solutions that concern many people. OTOH I don't like to post random picts or have portraits of my family or cats posted... I'll try to post some landscape (with the WAs) or landscape details (with the teles) whenever I'll have time to do so...

Also... Raw you may forget about it, it will be Jpegs from Raws developed with Focus software and 100% "cuts" out of them...

[lowep]

Excuse me if this is a dumb question but I would like to ask anyway what happens in terms of crop factor and 35mm equivalent focal lengths when you mount a Contax 645 lens (for example the good old Zeiss 80mm f2?) on a FF Canikon DSLR and also what about if the same lens was mounted on an APS-C sensor camera?

[fdisilvestro]

The focal lenght of the lens does not change when using different sensor sizes. An 80 mm is always an 80mm, so the Zeiss 80mm F/2 will be the same as an 80mm lens made for 35 mm

The "lens equivalence" concept is related to "angle of view" or Field of view, because many people are familiar with 35mm, where a 50mm is a normal, 80-100 medium tele, 28mm wide angle and so on.

When you mount the 80mm on a APS-C, it will still be an 80mm, but the angle of view will be similar to a 120mm on FF (considering 1.5x).
Comparing FF 35mm to medium format, an 80mm is a normal lens in medim format but a short tele for FF 35mm (in terms of angle of view).

More info here

[lowep]

thanks for explaining this and the useful link. If I understand right this means the angle of view of the same 80mm lens would be a whopping 180mm on an aps-c body... maybe good for photographing sea lions?