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Thread: Image Circle of Contax 645 Lens

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    Image Circle of Contax 645 Lens

    I am very interested in the Alpa upcoming Contax Shift mount for 12FPS. Would like to know how big the IC for Contax 45-90 and also 35mm. Does anyone has any experince or specification of these 645 lens? I am going to pair the lens with 44x33 CMOS sensor back.

    In regards to IQ, how does the 45-90mm and 35mm perform at the corner? Thanks in advance.

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    Re: Image Circle of Contax 645 Lens

    Alpa was so nice to borrow me their Contax 645 version of the mount for the FPS which allows 12mm shift movements in all directions (left/right and up/down independingly and simultanously) and I did tests with some lenses (all with IQ180). The Contax 645 shift adapter is technically not yet the mass :-) production version but the preliminary version they showed at Photokina 2014. Of course it has the latest firmware to control the aperture (and focus if required by the user!) of the Contax 645 lenses.

    I did initial tests of several Contax 645 lenses from 35 mm to 210 mm but here to mention only the wide angle Distagons 35f3.5 and 55f3.5. Sorry Kim I don't own (any longer) the 45-90. All Contax 645 lenses work perfectly with the FPS, the camera recognizes the lens with its correct maximum aperture, the aperture can be choosen in the FPS menu (just like with Canon lenses using the FPS Canon EF mount), the aperture ring at the lens is out of function.

    For my first tests I used f11 for all shots and auto-stitched in Photoshop CS6 always four pictures in landscape orientation after opening them in ACR and doing some basic adjustments (use equal color temperature, add some clarity, unsharp mask 100% 0,5 pixel, automatic reduction of chromatic aberation):*
    - left 12mm
    - left 12mm + up 12mm
    - right 12mm + up 12mm
    - right 12mm
    This results in images 76mm wide and 52,5mm high (stiched sensor size) with about 150 MP resolution.

    I added rulers to the images to better determine the sharp image circles and the total image circles.

    Following links to the stiched files:

    Contax 645 35f3.5

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    total image circle: about 81 mm
    sharp image circle: about 78 mm

    I added a version of the same file reduced to IQ250 sensor size plus 12mm shift to all directions.

    https://dl.dropboxusercontent.com/u/...-r12-IQ250.jpg

    As you can see, the image is perfectly sharp within +/- 12mm right/left OR up/down, just both together leaves the corners outside the total image circle.

    Enclosed a second test image by the Contax 645 35f3.5.

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    This time at f16 and camera and sensor in portrait orientation, four pictures stiched together (center, 12 mm right, 12 mm right + 12 mm up, 12 mm up). Here I removed/reduced the geometrcial distortion of the single images first using the Alpa lens corrector plug-in for Photoshop before stiching them together. That works pretty well as one can see. At f16, the usable sharp image circle enlarges to about 80 mm (but of course the general sharpness is reduced slightly due to diffraction).

    (Comment: The pre-series Alpa Contax 645 shift adapter is completely anodized in black but lacks inside matt coating. This leads to internal reflexions/flare which reduces the contrast especially of the super-wide angle 35 mm lens and even reflected stripe patterns can be seen in the sky in the left upper corner of the image. The series version of course will have the deeply black matt coatings which are standard for Alpa products.)

    Contax 645 55f3.5

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    total image circle: about 93 mm
    sharp image circle: about 76 mm

    The total image circle of the 55 is much larger than the 35, but the sharp image circle is slightly smaller. Also very useful with the Contax 645 shift adapter for the FPS.

    The shift adapter works excellent. Alpa plans to release it (and the Hasselblad H and Rollei Hy6 versions) within the next months.

    Christoph
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    Re: Image Circle of Contax 645 Lens

    Thank you so much, Chris, for such a comprehensive test!!!!
    How do you find the image quality? Does it compare well against Rodenstock HR lens on the Credo 50/IQ250 back?

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    Re: Image Circle of Contax 645 Lens

    Another question, Chris, is where do you find the Lens Correction Profile for the digital back and Contax lens?

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by chrismuc View Post
    Alpa was so nice to borrow me their Contax 645 version of the mount for the FPS which allows 12mm shift movements in all directions (left/right and up/down independingly and simultanously) and I did tests with some lenses (all with IQ180). The Contax 645 shift adapter is technically not yet the mass :-) production version but the preliminary version they showed at Photokina 2014. Of course it has the latest firmware to control the aperture (and focus if required by the user!) of the Contax 645 lenses.

    I did initial tests of several Contax 645 lenses from 35 mm to 210 mm but here to mention only the wide angle Distagons 35f3.5 and 55f3.5. Sorry Kim I don't own (any longer) the 45-90. All Contax 645 lenses work perfectly with the FPS, the camera recognizes the lens with its correct maximum aperture, the aperture can be choosen in the FPS menu (just like with Canon lenses using the FPS Canon EF mount), the aperture ring at the lens is out of function.

    For my first tests I used f11 for all shots and auto-stitched in Photoshop CS6 always four pictures in landscape orientation after opening them in ACR and doing some basic adjustments (use equal color temperature, add some clarity, unsharp mask 100% 0,5 pixel, automatic reduction of chromatic aberation):*
    - left 12mm
    - left 12mm + up 12mm
    - right 12mm + up 12mm
    - right 12mm
    This results in images 76mm wide and 52,5mm high (stiched sensor size) with about 150 MP resolution.

    I added rulers to the images to better determine the sharp image circles and the total image circles.

    Following links to the stiched files:

    Contax 645 35f3.5

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    total image circle: about 81 mm
    sharp image circle: about 78 mm

    I added a version of the same file reduced to IQ250 sensor size plus 12mm shift to all directions.

    https://dl.dropboxusercontent.com/u/...-r12-IQ250.jpg

    As you can see, the image is perfectly sharp within +/- 12mm right/left OR up/down, just both together leaves the corners outside the total image circle.

    Enclosed a second test image by the Contax 645 35f3.5.

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    This time at f16 and camera and sensor in portrait orientation, four pictures stiched together (center, 12 mm right, 12 mm right + 12 mm up, 12 mm up). Here I removed/reduced the geometrcial distortion of the single images first using the Alpa lens corrector plug-in for Photoshop before stiching them together. That works pretty well as one can see. At f16, the usable sharp image circle enlarges to about 80 mm (but of course the general sharpness is reduced slightly due to diffraction).

    (Comment: The pre-series Alpa Contax 645 shift adapter is completely anodized in black but lacks inside matt coating. This leads to internal reflexions/flare which reduces the contrast especially of the super-wide angle 35 mm lens and even reflected stripe patterns can be seen in the sky in the left upper corner of the image. The series version of course will have the deeply black matt coatings which are standard for Alpa products.)

    Contax 645 55f3.5

    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg

    total image circle: about 93 mm
    sharp image circle: about 76 mm

    The total image circle of the 55 is much larger than the 35, but the sharp image circle is slightly smaller. Also very useful with the Contax 645 shift adapter for the FPS.

    The shift adapter works excellent. Alpa plans to release it (and the Hasselblad H and Rollei Hy6 versions) within the next months.

    Christoph
    Thanks!!! Where can I find the Lens Corrector Profile for Conax Lens?

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    Re: Image Circle of Contax 645 Lens

    You can download the free photoshop plug in from the Alpa website or use capture one 8 which apparently is using the Alpa lens corrector for the contax lenses. Works like a charm

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    Re: Image Circle of Contax 645 Lens

    Hi Kim,

    I use the FPS only with Canon TSE, Contax 645, Hasselblad V and other MF lenses, but I don't use Rodenstock HR lenses. Also I don't have any experience with the IQ250 sensor but the pixel size of the 250 (5.3 um) is quite the same same like the 180/280 (5.2 um), so regarding sharpness requirement they are very similar.

    The Alpa lens corrector plugin for Photoshop can be downloaded here:

    ALPA of Switzerland - Manufacturers of remarkable cameras - ALPA Lens Corrector

    Btw, the current version of C1 (8 I assume) also can correct the distortions (with and without shift) of Contax 645 (and many other lenses), the correction parameters come with the software (no plugin required).

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    Re: Image Circle of Contax 645 Lens

    Hi Grischa, thx, I was too slow writing :-)

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    Re: Image Circle of Contax 645 Lens

    Thank you so much for such detail insight into this setup. I am pretty convinced with the IQ.

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    Re: Image Circle of Contax 645 Lens

    Chris, are you based in Guangzhou?

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    Image Circle of Hasselblad H Lenses on Alpa FPS and shift adapter?

    I recently saw the Alpa Shift adapter for Hasselblad H lenses

    ALPA of Switzerland - Manufacturers of remarkable cameras - Photokina 2014


    and was wondering if anybody had information on the image circle of these lenses?

    They obviously have a much larger image circle than 645 otherwise a "shift" adapter would be pointless..

    I noticed a similar post by "kimyeesan" and see that "chrismuc" has had access to a preproduction version of the Contax 645 shift adapter and these results look very impressive!!


    The one difference that I am wondering between these two camera systems (presuming that both have suitable image circles to be used with the shift adapter), is whether the Hasselblad H lenses will flash sync at their maximum sync speed on the Alpa FPS (using the lenses leaf shutters), even when using full shift on the Alpa adapter?

    If so, that would be very cool indeed


    Thanks so much, if anybody has any information, would be greatly appreciated!

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    Re: Image Circle of Contax 645 Lens

    As an ex-Contax 645 user, and current Alpa system (inc FPS) user, I have to caution your enthusiasm on this path, in that the old film lenses, mostly designed in the 1980's, or 90's at best, are simply not up to modern MF digital needs. They can give an 'interesting' look, and maybe a few of them, a very few mind you, are acceptable in their sharpness, but none will be able to resolve what a current generation Rodenstock Tech lens is capable of.

    What they can do is provide a faster aperture, and affordability, (remember to factor in this pricey adapter!) but don't expect results that compare to a dedicated modern tech lens in resolution.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by narikin View Post
    As an ex-Contax 645 user, and current Alpa system (inc FPS) user, I have to caution your enthusiasm on this path, in that the old film lenses, mostly designed in the 1980's, or 90's at best, are simply not up to modern MF digital needs. They can give an 'interesting' look, and maybe a few of them, a very few mind you, are acceptable in their sharpness, but none will be able to resolve what a current generation Rodenstock Tech lens is capable of.

    What they can do is provide a faster aperture, and affordability, (remember to factor in this pricey adapter!) but don't expect results that compare to a dedicated modern tech lens in resolution.
    I understood that. It's the opportunity to use zoom lens, therefore more versatile that draw me to this path.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by narikin View Post
    As an ex-Contax 645 user, and current Alpa system (inc FPS) user, I have to caution your enthusiasm on this path, in that the old film lenses, mostly designed in the 1980's, or 90's at best, are simply not up to modern MF digital needs. They can give an 'interesting' look, and maybe a few of them, a very few mind you, are acceptable in their sharpness, but none will be able to resolve what a current generation Rodenstock Tech lens is capable of.

    What they can do is provide a faster aperture, and affordability, (remember to factor in this pricey adapter!) but don't expect results that compare to a dedicated modern tech lens in resolution.
    In anycase, I have been using the TSE canon lens. The example of the contax lens is way sharper already to the canon specimen. So, if I can accept Canon's I think I can accept Contax. Hahhaha Thanks though for the fair and valid warning!

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by kimyeesan View Post
    In anycase, I have been using the TSE canon lens. The example of the contax lens is way sharper already to the canon specimen. So, if I can accept Canon's I think I can accept Contax. Hahhaha Thanks though for the fair and valid warning!
    What aperture are you shooting the TSE's at? I'd recommend f/11-16 for the best results.

    There is a significant difference on the 24 even just between f/8 and f/11 -

    Copyright Gerald Donovan 2013. All rights reserved.



    Kind regards,


    Gerald.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by gerald.d View Post
    What aperture are you shooting the TSE's at? I'd recommend f/11-16 for the best results.

    There is a significant difference on the 24 even just between f/8 and f/11 -

    Copyright Gerald Donovan 2013. All rights reserved.


    Kind regards,


    Gerald.
    Hi, Gerald, I always shoot f11 or smaller, but I do find that I need to dial the focus back a bit from the end turn of the canon focus ring as it focus way pass infinity... or am I wrong? it realy do have to pair with the Credo50 to check critical focus everytime... even at f11...

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by kimyeesan View Post
    Hi, Gerald, I always shoot f11 or smaller, but I do find that I need to dial the focus back a bit from the end turn of the canon focus ring as it focus way pass infinity... or am I wrong? it realy do have to pair with the Credo50 to check critical focus everytime... even at f11...
    You're not wrong - the TSE's focus way past infinity, and the tiniest of movements can make a huge difference. They are very, very sensitive.

    Kind regards,


    Gerald.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by gerald.d View Post
    What aperture are you shooting the TSE's at? I'd recommend f/11-16 for the best results.

    There is a significant difference on the 24 even just between f/8 and f/11 -

    [url=http://08.ae/panos/24TSEvs23HR/HRTSE.html]

    Kind regards,

    Gerald.
    Hi Gerald,

    I did a detailed comparison of the TS-Es (17mm, 24mm II, 90mm) and the Contax-Zeiss PC-Distagon 35mm on Luminous Landscape Forum (http://www.luminous-landscape.com/forum/index.php?topic=93273.0). I attach a compilation of crops from different parts of images with 10mm of vertical shift. There is more about this on LL.

    My recommendation:
    Unshifted position: for a flat subject I would use all lenses at f8. This will change of course if you have a 3-dimensional subject that needs more depth of field.
    Shifted position (+10mm): for a flat subject the PC-Distagon and the 90mm can be used at f8 even shifted. The 17mm and 24mm need to be stopped down to f11 for better corner sharpness. From about 3 or 4mm of shift f11 is better with the 17mm and 24mm.

    These tests were for the use on an A7R. Used on an Alpa FPS and a 44x33mm sensor like the IQ 250 you get into the not-so-good part of the image circle too often. That was the reason why I decided to stay with the A7R (or the upcoming 5DsR).

    I could get my hands on the Contax 35mm for 645 format on an Alpa FPS and the prototype of the Alpa Shift-Adapter too. I was very impressed. As shown by others in this thread it is much sharper in the outer part of the image circle than the TS-Es. I would say this lens is definitely up to the needs of modern sensors. But I need a wider lens for architecture photography too often. And there is no wider option in the contax system.

    Best regards - Marc

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by kimyeesan View Post
    I understood that. It's the opportunity to use zoom lens, therefore more versatile that draw me to this path.
    I used to have that Contax MF zoom - pretty good lens, and not bad value for the glass/ elements involved. Heavy though. No idea if it up to digital or not, sold it many years ago.

    All I can say is stay away from current generation Rodenstock Tech lenses. Especially the 90mm HR-SW. You will not be happy with any Contax or Hasselblad lens once you've seen what that can do.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by marc aurel View Post
    Hi Gerald,

    I did a detailed comparison of the TS-Es (17mm, 24mm II, 90mm) and the Contax-Zeiss PC-Distagon 35mm on Luminous Landscape Forum (A comparison of four shift lenses on the A7R). I attach a compilation of crops from different parts of images with 10mm of vertical shift. There is more about this on LL.

    My recommendation:
    Unshifted position: for a flat subject I would use all lenses at f8. This will change of course if you have a 3-dimensional subject that needs more depth of field.

    <snip>

    These tests were for the use on an A7R. Used on an Alpa FPS and a 44x33mm sensor like the IQ 250 you get into the not-so-good part of the image circle too often. That was the reason why I decided to stay with the A7R (or the upcoming 5DsR).
    Best regards - Marc
    Hi Marc -

    It's very important to stress the sensor here. With the 24 TSE at least, there is a significant difference on FF MFDB when you go from f/8 to f/11, and another improvement from f/11 to f/16.

    The diagonal of the MFDB is 14mm longer than that of the A7R, so it's perhaps not surprising that if you're "only" shifting 10mm on the A7R you're not getting into the zone where stopping down starts to make a big difference.

    Looking at your test image, I'm assuming that you're shifting up 10mm in portrait orientation - that means the image circle required to cover that shift is actually just 61mm.

    The TS-E image circles are a lot larger than that - they have to be a minimum of 67.2mm to cover the IQ180 used in my earlier linked example.

    It's great to see these lenses getting used on a wide range of cameras and formats - they are incredibly versatile - but care needs to be taken not to interpret results of tests on one format as being relevant to another. I wouldn't dream of shooting these lenses at f/8 on FF MFDB unless I wasn't at all worried about the corners.

    Kind regards,


    Gerald.

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by gerald.d View Post
    Hi Marc -

    It's very important to stress the sensor here. With the 24 TSE at least, there is a significant difference on FF MFDB when you go from f/8 to f/11, and another improvement from f/11 to f/16.

    The diagonal of the MFDB is 14mm longer than that of the A7R, so it's perhaps not surprising that if you're "only" shifting 10mm on the A7R you're not getting into the zone where stopping down starts to make a big difference.

    Looking at your test image, I'm assuming that you're shifting up 10mm in portrait orientation - that means the image circle required to cover that shift is actually just 61mm.

    The TS-E image circles are a lot larger than that - they have to be a minimum of 67.2mm to cover the IQ180 used in my earlier linked example.

    It's great to see these lenses getting used on a wide range of cameras and formats - they are incredibly versatile - but care needs to be taken not to interpret results of tests on one format as being relevant to another. I wouldn't dream of shooting these lenses at f/8 on FF MFDB unless I wasn't at all worried about the corners.

    Kind regards,

    Gerald.

    Hi Gerald,

    of course you are right - you can not simply take results from one sensor size to another. I didn't mean to do that. I was just trying to give an impression of what happens when you use the outer parts of the image circle and present the results in a way that can be easily consumed.

    But the pixel size of the A7R is very close to that of the IQ250 that I referred to (4,9 vs. 5,3). Both have no AA-filter and are made by Sony. So resolution on pixel level should be similar if you use the same lens and aperture. The image that the lens projects is the same, you just use a larger part of it.

    With that in mind - I admit you're right. My recommendation for f8 unshifted would be wrong for a MF sensor - because you use parts of the sensor that are further away from the centre. The corner of an unshifted IQ180 sensor is 33,6mm from the centre, the corner of an unshifted IQ 250 is 27,5mm from the centre - very close to where I took my crop from. And for that crop - 30mm from the centre - yes, f16 looks even better than f11. But the centre gets a bit worse already at f11 because of diffraction, and a bit more at f16. So there is a tradeoff. From what I have seen - the Contax 35mm for 645 holds sharpness better and does not need to be stopped down to f16 to do this. As much as I love the TS-Es - they are great and offer extreme wide angles, but they are not perfect for a MF sensor in my opinion.

    I would be really interested to see a well done comparison between the Contax 35mm for 645 versus the HR Digaron 32mm with an IQ 250.

    Best regards - Marc
    Last edited by marc aurel; 7th February 2015 at 00:23.

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    Re: Image Circle of Contax 645 Lens

    Marc: comparison Rodenstock 32 vs. Contax 645 35 w/ 44x33mm Sony sensor

    image circle & color cast:
    Voidschatter tested here

    http://www.getdpi.com/forum/medium-f...-artifact.html

    the Rodie 32 with the Sony 50MP back and found that the maximum shift with acceptable (= correctable) amount of corner color shift is 12mm rise at landscape orientation. This means the Rodie 32 in combination with a 50MP CMOS back has a usable image circle of 72mm.

    The Contax 645 35's image circle is a bit larger with 78mm with allows also full lateral shifts of 12mm (without color cast correction in post!) or combinations of left/right and up/down to a certain extent.

    sharpness:
    At f11 diffraction limits the contrast at 40 l/mm to 69 %, therefore I expect sharpness of the two lenses to be quite similar.

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    Re: Image Circle of Contax 645 Lens

    I want to proceed reporting about my tests using 645 and 6x6 lenses mounted to the prototype Alpa Contax shift adapter / Alpa FPS / IQ180.

    First the list of tested lenses:

    1. Contax 645 (mounted directly to the Contax shift adapter)

    Contax 645 35f3.5 Distagon
    Contax 645 55f3.5 Distagon
    Contax 645 80f2 Planar
    Contax 645 120f4 Apo Makro-Planar
    Contax 645 140f2.8 Sonnar
    Contax 645 210f4 Sonnar

    2. Mamiya 645 (lens mount converted to Contax 645)

    Mamiya 645 200f2.8 Apo

    3. Hasselblad V (with Hasselblad V - Contax 645 adapter)

    CF 50f4 FLE Distagon
    CF 100f3.5 Planar
    CF 150f2.8 Sonnar
    CF 180f4 Sonnar

    Like mentioned before, I always stiched four pics to one file.
    - left 12mm
    - left 12mm + up 12mm
    - right 12mm + up 12mm
    - right 12mm
    This results in images 76mm wide and 52,5mm high with about 150 MP resolution.

    Following links to the stiched files:

    Contax 35f3.5 and 55f3.5
    see previous post in same thread.

    Contax 80f2
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 86mm
    sharp image circle: about 74mm

    Contax 120f4 Apo Macro
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 100mm
    sharp image circle: about 79mm

    Contax 140f2.8*
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 81mm
    sharp image circle: about 78mm

    Contax 210f4
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 99mm
    sharp image circle: about 79mm

    Hasselblad V lenses via a Hasselblad V to Contax 645 adapter:

    Hasselblad V 50f4 FLE
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 96mm
    sharp image circle: about 78mm

    Hasselblad V 100f3.5
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 100mm
    sharp image circle: about 75mm

    Hasselblad V 150f2.8
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 101mm
    sharp image circle: about 78mm

    Hasselblad V 180f4
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 100mm
    sharp image circle: about 92mm

    Mamiya 645 lens (converted to Contax 645 mount):

    Mamiya 645 200f2.8 Apo
    https://dl.dropboxusercontent.com/u/...2%2Brulers.jpg
    total image circle: about 91mm
    sharp image circle: about 88mm
    (Att: I focussed not exactly on front of the center car but eventually slightly behind.)

    Unfortunately the motive with the cars in the BMW exhibition hall is not the most useful because not always parts of the motive are in the relevant area of depth of field outside the center.
    So while it’s easy to see the total image circle, it is a bit difficult for the longer focal lengths to see well the sharp image circle.
    I have to do the test again with a plain house wall with detailed structure.

    Also the curvy Zaha Hadid architecture of the building covers any information about geometrical lens distortions:-)

    In case of using a 44x33mm digital back (IQ150, IQ250, P40+, Credo 40, Credo 50, Hasselblad CFV-50 aso.), the image circles of all tested lenses despite the Contax 645 35f3.5 and the Contax 645 80f2 would be sufficient to cover full shifts in both directions at the same time!

    From the excel calculations you can see the maximum shifts horizontally and vertically within the sharp image circles.

    And I added a calculation for a 2.5 to 1 ratio panoramic picture by stiching two left and right shifted shots. The image circles of the tested lenses allow 13.000 to 16.000 pixel wide 2.5/1 pano pics with 72 to 106 MP resolution.

    I intend to use the Alpa Contax shift adapter mainly with the Contax 35, the Hasselblad 50 FLE, 100 and 180. Together with the 17 & 24 TSE lenses using the Alpa Canon mount for the FPS, this provides a nice range of wide angle to medium focal length lenses with certain shift capabilities, good sharpness, lack of color cast, reasonable priced (after heavily investing in the cam + two mounts and the back ... ;-) without using a dedicated tech cam and Schneider/Rodenstock lenses.

    Enjoy,

    Christoph

    link to the image circles coz the thumbnail pic is too small
    https://dl.dropboxusercontent.com/u/...ge-Circles.png
    Last edited by chrismuc; 9th February 2015 at 01:39.
    Likes 2 Member(s) liked this post

  24. #24
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    Re: Image Circle of Contax 645 Lens

    Christoph,
    You got to stop this , soon there are no more Contaxt lenses on the market :-)
    Kidding aside thanks for you great contributions , you are a living well of knowledge.
    I did not expect the 32 HR to shift less on the IQ250 as compared to the IQ260
    Again thanks

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    Re: Image Circle of Contax 645 Lens

    Thx Grischa,

    actually my purpose is to encourage

    Zeiss (+ Kyocera?)

    - to release an updated version of their 645 camera (modern AF)
    - to update their 645 lens line (add 25, update 45 and 210)

    Sony

    - to release a 54x40mm version of their 44x33mm CMOS sensor

    Phase One

    - to reconsider their back prices

    :-)

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    Re: Image Circle of Contax 645 Lens

    Christoph and voidshatter -

    to both of you: thank you very much for your great work. That helps a lot.

    Marc

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by narikin View Post
    I used to have that Contax MF zoom - pretty good lens, and not bad value for the glass/ elements involved. Heavy though. No idea if it up to digital or not, sold it many years ago.

    All I can say is stay away from current generation Rodenstock Tech lenses. Especially the 90mm HR-SW. You will not be happy with any Contax or Hasselblad lens once you've seen what that can do.
    Too late, I have HR 23, 32, 50 and 70 and about to get the new HRSW 90...

    I can understand what it can do and yes, it's spectacular.

    But I really like those Zoom lens opportunity and also as a package, SLR lens tends to be more transportable and also more 'solid' built... not sure if I used the correct word or not...

  28. #28
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    Re: Image Circle of Contax 645 Lens

    I am fortunate enough to have tried out the Pre production version of the Contax Shift Adaptor today. I am very happy to report that it is an amazing piece of kit. Albeit that it still need some work in terms of ergonomics. Contax lens is amazing!

    Contax 645 [email protected] 3 Image Stitched
    This lens is the lowest resolving lens of the bunch, as I found out today.

  29. #29
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    Re: Image Circle of Contax 645 Lens

    Contax 645 Distagon 35mm f/3.5 + Credo 50


  30. #30
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    Re: Image Circle of Contax 645 Lens

    Contax 645 APO Makro Planar 120mm


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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by chrismuc View Post
    Thx Grischa,

    actually my purpose is to encourage

    Zeiss (+ Kyocera?)

    - to release an updated version of their 645 camera (modern AF)
    - to update their 645 lens line (add 25, update 45 and 210)

    Sony

    - to release a 54x40mm version of their 44x33mm CMOS sensor

    Phase One

    - to reconsider their back prices

    :-)
    Excelent information Chris... very helpful for those that expect to use their Contax lenses on Cambo Actus too, if Cambo will release a Contax mount adapter version of their battery powered automatic aperture control lens adapter.

    I believe that Contax manufacturing rights are 10 years old by the 31st of December this year... I think that the international law gives the right to Zeiss (owner of Contax rights) to overcome Kyocera contracts after 31/12/2015 and thus, it is very possible to see a resurrection of the C645 system if another maker or Zeiss itself decides to enter the MF market with an alternative camera platform.

    In my opinion, C645 camera needs very little improvements in order to be adapted on todays standards, an up today AF system is the major spec that it lacks.

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    Re: Image Circle of Contax 645 Lens

    I have been reliably informed that Zeiss have no interest at all in MF lens production nowadays - the numbers are just far too small to make it worthwhile. The money is all in FF compatibles.

    (The fiasco of the Zeiss-Sinar M lens range, add weight to that opinion. I doubt 300 of these MF Zeiss lenses were sold worldwide. Shame)

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by narikin View Post
    I have been reliably informed that Zeiss have no interest at all in MF lens production nowadays - the numbers are just far too small to make it worthwhile. The money is all in FF compatibles.

    (The fiasco of the Zeiss-Sinar M lens range, add weight to that opinion. I doubt 300 of these MF Zeiss lenses were sold worldwide. Shame)
    That maybe true, but surely Zeiss are interested for Contax name not to "die". If another company is interested to replace Kyocera, then there is no risk for Zeiss as to license them for resurrecting the name.

    In fact, there maybe interest from Leica to do so... If one thinks about it, Leica needs a system as to "bridge" Leica S with Sinar products. The resurrection of Contax from a maker like Leica could both provide a platform for Sinarbacks to be used on an "in-family" MF platform and also has a lens system that is fully dedicated with the Leica S series of cameras.

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    Re: Image Circle of Contax 645 Lens

    In fact a lens line like Contax, as Chris states above, maybe perfect for Sinar to enter the "small view camera" market after Cambo (Actus) and Arca (Universalis) did. Surely one can't expect Sinar not to compete with Arca or Cambo in the same field.

    Lets not forget that Leica now has the T-series in production of which the mount is also a mirrorless that can take a FF sensor, with C645 lenses and a focal plane shutter the T-series can be a perfect supplement for a "small" Sinar pro view camera platform of which the image area could be future upgraded by using an MFDB (multishot?) on it.

    Surely, the work that Leica does now with its 007 CMOS sensor and its LV capabilities, is expected to pass on Sinarbacks in the near future them being "family members".

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by T.Dascalos View Post
    I believe that Contax manufacturing rights are 10 years old by the 31st of December this year... I think that the international law gives the right to Zeiss (owner of Contax rights) to overcome Kyocera contracts after 31/12/2015 and thus, it is very possible to see a resurrection of the C645 system if another maker or Zeiss itself decides to enter the MF market with an alternative camera platform.
    the name rights went back to zeiss, several years ago, to my knowledge.

    i also see little hope that zeiss would lease the name again to make another MF system with updated C645 lenses, as much as i would hope so!

    as it has already been stated, a C645 II body would need a modern AF system, more power efficient electronics and tada, what else do you need.
    i love my contax for its simplicity!

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by drevil View Post
    the name rights went back to zeiss, several years ago, to my knowledge.

    i also see little hope that zeiss would lease the name again to make another MF system with updated C645 lenses, as much as i would hope so!

    as it has already been stated, a C645 II body would need a modern AF system, more power efficient electronics and tada, what else do you need.
    i love my contax for its simplicity!
    Although one can't be sure on what was the agreement between Zeiss and Kyocera or who was responsible for the discontinuation of the product line, I remember Zeiss claiming on their web side until 5 years ago that they own the name "Contax", I don't think that there was ever name rights that where passed to another company (or Kyocera) from Zeiss. To my knowledge there was a contract so that Kyocera would produce products approved by Zeiss and market them which lasted for several decades and that production was stopped by Kyocera because it was not profitable to them.

    I remember once a Phase One executive that happened to be on a conversation for the matter where I was present, that Phase One offered a good amount of money to Kyocera so that they would retire from the contract with Zeiss and resurrect Contax by making a new contract with Zeiss (Zeiss was in agreement for that), but it seems that Kyocera wasn't satisfied with the compensation and P1 moved to invest on Mamiya because of that.

    To my believe, there is some time under law (which I believe is of 10 years) that there is automatic disengagement from the contract between Zeiss and Kyocera. I also know that servicing of Contax products in Europe was done by Tritec (using genuine parts) in Germany and that it was authorised by Zeiss.

    Never the less, Contax ergonomics and lens quality has continuously satisfied me for the last 10 years and It never passed from my mind to drop the system for another. If a new body would be introduced, I would of course expect it to have a better AF system (the lenses become extremely fast and accurate focusing when used on my Nikons via the JAS adapter I recently got), rechargeable battery with more life, permanent mirror lock to use with multishot backs for while the process lasts and perhaps (even) faster shutter so that sync speed could be risen further. I would surely wouldn't want the ergonomics or the design to change... I wouldn't even complain if Av mode would be dropped completely.

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    Re: Image Circle of Contax 645 Lens

    i was in mail contact with zeiss once, they told me the name rights are back at zeiss now and it was especially pointed out that zeiss never made any cameras themselves, never, it was always other companies using the name.

    i also heard that phase was heavily interested in aquiring contax(kyocera) technology instead of mamiya

    but as already said, zeiss seems not interested anymore in investing into MF lenses. they make a big buck of money these days with 35mm lenses and smaller.

    sad but true

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by drevil View Post
    but as already said, zeiss seems not interested anymore in investing into MF lenses. they make a big buck of money these days with 35mm lenses and smaller.

    sad but true
    It certainly seems that MF lenses market has shrunk considerably during the past decade... MF camera market is much smaller in the digital era than they used to be with film, but this may be about to change soon... The recent introduction of Cambo Actus & Arca universals is expected to be followed by other makers soon (Sinar, Silvestri ...etc). There is also a tendency for larger sensors for cinema/video use... Lets not forget that cinema was always a market that historically interests Zeiss.

    If all the above will be combined with a possible C645 resurrection, I find it very possible that Zeiss interest on that market will be attracted back, especially as they already have very good designs to be based on from the past and a lot of new technology to develop them further, without investing from start to create a line.

    IMO it all has to do with how promising the (possible) investor would be. I believe that if the investor would be a company with "heavy" name (like Leica) and if Sony (a traditional Zeiss companion) will decide to join the group of makers with larger sensor cameras for video/cinema, then it would certainly be on Zeiss interest to re-enter the larger image circle lenses market.

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    Re: Image Circle of Contax 645 Lens

    I am new to GetDPI and this thread. I have four Contax 645 lenses and a converted NAM-1 adapter to Canon mount. I also just purchased a HCam Mirex Canon to E-mount adapter (version 2) to use these Contax lenses (T&S) with my Sony A7RII and A7II. I belatedly discovered that putting the Mirex into the equation means no f-stop adjustment is possible (since this is electronically by 'wire' with 645 lenses).

    Stefan Streib put me onto this thread and so I am asking for feedback on this issue - he mentioned that Christoph Kugler has some experience with this situation. Cheers.

  40. #40
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    Re: Image Circle of Contax 645 Lens

    Hi Alan, welcome using Contax 645 lenses on a non-Contax 645 camera ;-)

    Using Contax 645 lenses

    - either w/ Mirex Contax 645 - Canon EF shift adapter + Canon EF camera
    - or w/ Contax NAM-1 adapter (Conorus converted) + Hartblei/Mirex Canon EF - Sony E shift adapter + Sony E camera

    you will have to mount the Contax 645 lens first either to a Contax 645 camera or via the Contax NAM-1 adapter to a Canon EF camera, set they wanted aperture (e.g. f11) at the lens barrel, push the DOF button on the camera (so the aperture will close to the desired value) and unmount the lens. The lens will stay at this aperture.

    Actually the same procedure like using a Canon EF lens (e.g. the TSE lenses or the 11-24) with the Hartblei/Mirex Canon EF - Sony E shift adapter on a Sony E camera

    This is of course a bit uncomfortable but for architecture, interior design and landscape where you mainly would use an aperture around f8 ... f13 it is not such a big drawback to pre-set it. And using life view, the focusing at such rather closed aperture still work very well.

    Enjoy, Christoph
    Last edited by chrismuc; 26th September 2015 at 00:31.

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    Re: Image Circle of Contax 645 Lens

    Thank you Christoph - that is everything I need to know. I have been using the Contax 645 120mm Macro with the Sony a7RII (via NAM-1) and I love this lens, even though I have the Sony FE 2.8 Macro in some circumstances I prefer the Contax. I now can get started using the 645 35mm with the Mirex, my first foray into Tilt/Shift - inspired by Satoru Murata's images.

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    Re: Image Circle of Contax 645 Lens

    Anybody know how much "rise" you can get when using the Contax PC 35mm on a 33mm x 44mm back?

    Thanks in advance!

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by wallpaperviking View Post
    Anybody know how much "rise" you can get when using the Contax PC 35mm on a 33mm x 44mm back?
    While I can't answer that question, in a related vein, I can show that a Contax N 17-35/f2.8 zoom at 35mm/f8 and focused at infinity, will not only cover a 33x44 sensor, but do so and still have a bit of room for movements:



    FYI, the illumination circle is actually a bit larger still, but the lens has a baffle installed over the rear element to limit the coverage to only the area where the image quality still holds up.

    Even at 21mm/f8, there's still enough coverage for a 33x44 sensor with maybe a millimeter or two left over for movements:



    Mind you, I wouldn't necessarily recommend this lens for use with a sensor that large, but if you can find a camera to mount it on (its flange-to-sensor distance is 48mm) with a digital back on the other side, don't need a shutter (for example, I photograph mostly at night with long exposures) and really need a wider-than-35mm focal length, it's potentially an option to consider. It certainly has the characteristic Zeiss "look" and can get the job done with a single shot when it's not possible to stitch one's way to happiness when a wider FoV is necessary. <shrugs>

    (FWIW, I've been successfully using it on a [modified] Toyo VX23D view camera, with a Sony A7R serving as a poor-man's digital back, and there's plenty of room for movements when it's used with a modest 24x36 sensor.)

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    Re: Image Circle of Contax 645 Lens

    Very interesting indeed!

    And at 17mm?

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    Re: Image Circle of Contax 645 Lens

    any room for movements on a 24mm x 36mm sensor?

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    Re: Image Circle of Contax 645 Lens

    Quote Originally Posted by wallpaperviking View Post
    any room for movements on a 24mm x 36mm sensor?
    At 17mm, there is some room, but not a lot ... 3-4mm, max:



    The coverage is about the same at 18mm, but starts increasing at 19mm, where there's ~4-5mm of movement available.

    FYI, here's a test photo I took at 17mm, with ~3mm of rise, of a house down the street, using the A7R as a back:



    As you can see, there's some darkening of the upper corners starting, but for most photos, I can live with it. (Of course, for most of my nighttime photos, it's not an issue at all, what with the mostly black sky overhead and all, but YMMV.)

    But there's no way it will cover a 33x44 sensor.

    And for the moment, there's no way to control the electronic aperture with the lens mounted on the camera (although I'm working on that and expect to successfully transfer the guts of a Kipon adapter into my modified Toyo, where I am using a modified Contax N 26mm auto extension tube to mount the lens on a custom recessed board and a modified, generic, Sony E-mount auto extension tube to mount the body. Both of these mounts have electrical contacts built-in and use wires to connect them to the other side, so it's not a big deal to splice-in the Kipon circuitry. I actually have it all working on the bench, but because I've changed direction and am now building a smaller, lighter, custom camera around a modified Toyo Robos rear standard, I haven't bothered to install it into my existing camera. (And FYI, it's not possible to easily use the guts of a Fringer adapter, either, because the electrical contacts on both sides are connected directly to a single circuit board, unlike the Kipon, which mounts the contacts on each side on separate circuit boards and connect them to an intermediate circuit board via ribbon cables. As such, there is no easy way to separate one side of the Fringer adapter from the other side, whereas the Kipon adapter effectively does this at the factory. Which is a shame, because I was really hoping I could use it to control the apertures of both my Contax N and Contax 645 lenses when used with the same modified Toyo, but given my limited skill level with electronics, separate setups will be required instead. But I digress...)
    Last edited by Audii-Dudii; 17th September 2016 at 05:57.

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