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

[Theodoros]

I have to admit that if I didn't already have a huge C645 system (almost everything they ever made but the 350 lens which isn't among my considerations), I wouldn't consider the adapter... But since I've tried it, I've also have to admit that if I didn't own the C645 system but was familiar of the lens properties, as I am... then I would most certainly do the same...  My post was purely to share gained experience with people that don't... I tried my best to explain that resolution wise there is nothing worth considering to make the choice. But OTOH, I do know that the vast majority of "true" photographers are more than satisfied with the resolution they are now offered... Yet, I believe, that there's still a good part of very good photographers that don't think of resolution (as long as they already have more than they need) as being a first priority aspect when they choose a lens (I'm among them)... To them, I started this thread as to give them (the best I could) an idea of an alternative, which in my opinion is better too... and explain the reasons as to why I consider it as being better, so that they can judge themselves if my priorities match theirs...

OTOH. there is the big problem with many pros (me among them), where they have to carry lots of equipment to perform a certain task... Imagine for example one that has to carry all his FF system and all his MF and MFDBs and additionally his view camera and lenses for a project, just to use some of each system for parts of the project... Now what if the same pro. for the very same project, carries only his MF system, adds only a couple of FF bodies (one of them mirrorless) and a Cambo Actus (or Arca Universallis) with it and use his MF lenses for the lot? ...and then there is the matter of cost involved for that (very real) pro...

[EinstStein]

I had C645 350mm before, but it was stolen together with all my camera stuffs. I didn't recover that piece of glass.  The 350mm I had is not sharp at all, and focusing very slow. It's as heavy as an elephant too. I found Canon and Nikons is the way to go for super tele. -- not counting Leica's super tele lenses. They are too hard to find.

The C645 to Canon will be useful since I already have a pretty decent C645 system, but I fell $850 for an adapter is hard to justify.

[wallpaperviking]

Hi Theodoros,
                     You mention that

"Lets not forget that there is a Contax mount coming for Cambo Actus too and the wider image circle will be most welcome there if a Sony A is mounted on the Actus...."

Where did you hear this information? 

I know that they make a Contax 645 REAR mount for their digital back version but have only heard of a electronic Canon Eos FRONT mount for the Cambo Actus..

http://www.cambo.com/Html/products_photo/set01/english/internet/Item34418.html


I also know that Alpa are making a Contax 645 shift adapter for the Alpa FPS system.. 

Are you thinking of that? 

 

[EinstStein]

Apparently Theodore is very close to the JAS adapter maker.
Alias name of Steel.Chen?

[Theodoros]

Hi Theodoros,
                     You mention that

"Lets not forget that there is a Contax mount coming for Cambo Actus too and the wider image circle will be most welcome there if a Sony A is mounted on the Actus...."

Where did you hear this information? 

I know that they make a Contax 645 REAR mount for their digital back version but have only heard of a electronic Canon Eos FRONT mount for the Cambo Actus..

http://www.cambo.com/Html/products_photo/set01/english/internet/Item34418.html


I also know that Alpa are making a Contax 645 shift adapter for the Alpa FPS system.. 

Are you thinking of that? 

 

Steven Hendrix mentioned it on another conversation  a couple of months ago... then I checked the Conon Eos adapter that Campo is going to release during the second half of the year... and found out that ...it is not an EOS adapter (!!!) but rather a universal aperture control for all lenses that have electronic iris... If you check the picture of the ACB-CA that Cambo has published, you may notice that it is two parts... one is the iris control (ACB) and then there is a Canon (CA) mount in it which is interchangeable... Hence, you should expect an ACB-CO soon after, as the the name ACB-xx suggests...

No... I wasn't thinking of the Alpa...

[wallpaperviking]

Hi Theodoros,
                      Well I definitely like your theory, that would be amazing indeed! 

Unfortunately, I cannot see what you see

Looks like a Canon Eos electronic mount to me..  Also, I could not find any mention of Steven Hendricks talking about the Cambo Actus and a electronic Contax 645 mount..

Would you please be able to provide a link to that?

I know that Cambo are making a version of the Actus for MFDB and that probably includes one with a Contax 645 mount..  That is at the rear of the camera though..


Thanks again, I hope you are right and we will end up being able to use our Contax 645 lenses on the Cambo Actus

[Theodoros]

Actually I think ACB stands for Aperture Control Base.... I can't find the link either, but it was a conversation where both Steve and I where involved and Steve mentioned that Contax mount for the Actus is among Cambo's plans... I hope Steve will jump in the conversation and enlighten us both further... both for the Contax lens mount, as well as for the ACB....

[Steve Hendrix]

Actually I think ACB stands for Aperture Control Base.... I can't find the link either, but it was a conversation where both Steve and I where involved and Steve mentioned that Contax mount for the Actus is among Cambo's plans... I hope Steve will jump in the conversation and enlighten us both further... both for the Contax lens mount, as well as for the ACB....

You are correct, I did say that a Cambo Actus Lensboard for Contax 645 was being considered. That does not guarantee it will come to fruition, but we shall see. I will say this - if anyone who wants a Contax Lensboard for the Actus will PM me, I will put them together with my existing requests and provide them in bulk to Cambo.

On the surprising and positive news front, a Pentax 645 Lensboard (with aperture control lever for newer lenses) showed up today at our Atlanta office. Previously, I was selling a Cambo Nikon F Lensboard with a FotoDiox Pentax 645 Adapter (which fit together very nicely) to mount Pentax 645 lenses to the Actus. Now this is no longer necessary, there is a direct Pentax 645 Lensboard for the Actus, and also, Cambo just updated the Nikon F Lensboard with aperture control as well (previous version had no aperture control capability).


Steve Hendrix
Capture Integration

[Theodoros]

Of course one can mount Contax lenses on the Actus via the Canon ACB and use an additional JAS Contax to Canon adapter, but this would add to the cost and some of the lenses could have their image circle restricted...

[wallpaperviking]

I would personally love to see a Contax 645 lens board on the Actus

With regards to how these "electronic" adapters work, are they actually communicating with the camera?  Where is the connection between the lens board and the camera itself? 

Or is it somehow just altering the aperture and then you are needing to focus the camera in what is essentially "aperture stop down mode"?

So, if shooting at f16, focus would need to be done at f16...  as opposed to focusing being done wide open and then the lens stopping down at the moment of exposure..

Hope that makes sense : )

Of course one can mount Contax lenses on the Actus via the Canon ACB and use an additional JAS Contax to Canon adapter, but this would add to the cost and some of the lenses could have their image circle restricted...

This is not necessarily true..  I have been in contact with Steel before and there was a period there where his adapter was not able to effectively communicate with the Canon Metabones adapter... 

So possible but no guarantee..

Steve, any idea if the Pentax 645 has similar large image circle to that of the Contax 645 lenses?  Or is very much restricted to a 645 area?

[Theodoros]

I would personally love to see a Contax 645 lens board on the Actus

With regards to how these "electronic" adapters work, are they actually communicating with the camera?  Where is the connection between the lens board and the camera itself? 

Or is it somehow just altering the aperture and then you are needing to focus the camera in what is essentially "aperture stop down mode"?

So, if shooting at f16, focus would need to be done at f16...  as opposed to focusing being done wide open and then the lens stopping down at the moment of exposure..

Hope that makes sense : )

Of course one can mount Contax lenses on the Actus via the Canon ACB and use an additional JAS Contax to Canon adapter, but this would add to the cost and some of the lenses could have their image circle restricted...

This is not necessarily true..  I have been in contact with Steel before and there was a period there where his adapter was not able to effectively communicate with the Canon Metabones adapter... 

So possible but no guarantee..

Steve, any idea if the Pentax 645 has similar large image circle to that of the Contax 645 lenses?  Or is very much restricted to a 645 area?

There is total communication for all automatic aperture and AF through the CPU contacts... The adapter has a logic circuit build in, which supplies the power needed from the camera's battery to the lens and "fools" the camera's CPU contacts as if it was a dedicated lens used on it... Hence, focusing is at full aperture and the lens "stops down" automatically just before shutter is activated. S & P modes also work and meter correctly.

I wouldn't expect much difference between 6x4.5 MF lenses as far as image circle is concerned... never the less the image circle should be sufficient for a FF 35mm equal sensor... Let's not forget that the image circle is larger when a lens is focused to its minimum focusing distance and that the Actus has sufficient distance between its front and rear standards to compensate for focus to infinity.