Mounting APO Digitar lenses on P3 Lensboards

[Dick Roadnight]

I have been frustrated spending weeks trying to get a medium format digital view camera system set up and working, but nobody seems to want to mount  Schneider Apo-digitar lenses onto Sinar P3 lensboards - whenever you ask someone for a price they reply with questions and not answers.

I have a Hasselblad H3D11-50, but what goes on the back of the camera should not effect mounting lenses on the the front of the camera, especially if you intend to slide and stitch and use all the image circle.

The P3 system is an open system so anyone can manufacturer P3 compatible lensboards ( or P3 lens board compatible cameras)... but I do not know if anyone does.

I understand that the separation of the elements is critical, and so you need shims to adjust for different thicknesses of lens panel and /or shutter... and if the thickness of the lens panel is not standardized, this might be a problem.

If you mount a Schneider lens on a Schneider electronic shutter you would hope that it should not be too complicated.

If you buy a new lens I imagine that you would get installation instructions and a set of shims... if you buy a second hand lens, you might not get the shims or the instructions and it might be difficult to mount the lens for optimum performance.

If you buy a lens mounted on a P3 lens board - how do you check that it is mounted correctly?

Schneider do not seem to have an official UK dealer.

I an an engineer, and I have a vernier caliper, and I hope to have several Schneider APO-digitar lenses, so I thought it might be worth climbing up the learning curve and doing it myself (as if there was not enough to learn).

Has anyone any relevant advice or information?

Dick Roadnight

[Kumar]

Have you tried http://www.skgrimes.com/ ?

Cheers,
Kumar

[Dick Roadnight]

Have you tried http://www.skgrimes.com/ ?

Cheers,
Kumar

Thanks - I have heard of them, and they look like the type of outfit I am looking for, but I was hoping to find someone in the UK, or failing that, Europe.

[schaubild]

Why not asking Sinar directly?   www.sinar.ch

[Dick Roadnight]

Why not asking Sinar directly?   www.sinar.ch

If I cannot get any sence out of anyone in the UK, then Schneider or Sinar may supply me or give me information. I sent Schneider an e-mail at 07:00ish this morning (I expect that they do not have a bank holiday today) and have not had a reply.

I am in communication with Sinar UK = Image2output

Dick Roadnight

[Joe Behar]

Am I missing something here?

If your lens calls for a copal 0 or copal 1 board, you just simply order that board and mount the lens on it in exactly the same way we have been doing it on 4x5 for about 75 years now.

[schaubild]

If I cannot get any sence out of anyone in the UK, then Schneider or Sinar may supply me or give me information. I sent Schneider an e-mail at 07:00ish this morning (I expect that they do not have a bank holiday today) and have not had a reply.

I am in communication with Sinar UK = Image2output

Dick Roadnight

You are aware of the fact that it's the long easter weekend?

[j.miller]

Dick,
    Both Schneider Optics and Linos-Rodenstock offer their respective digital lenses, in a factory mounted configurations, including those to be used on the Sinar P-Series platform. Have you considered purchasing Schneider APO-Digitar lenses in this manor? With this configuration, Schneider procures the necessary Sinar-specific lens board and mounting components directly from Sinar AG.

Most all digital-specific lenses require a critical degree of precision in the mounting process, to maintain the necessary flange-focal distance and image field. This is especially true with those lenses that are 35mm in focal length or shorter.

The second-hand market can prove to be tricky, when and if you do not have the ability to properly test, and evaluate the lens.

With regard to the proper mounting of a lens, you are forced to rely on the manufacturers abilities to properly assemble, mount, and calibrate the lens(es) in question.

I cannot speak directly for Schneider's representation in the UK, however the Schneider Kreuznach website provides the following contact information:

GROSSBRITANNIEN - United Kingdom

JOHNSONS PHOTOPIA Ltd.
JP Distribution
Hempstalls Lane
GB - Newcastle
Staffordshire, ST5 OSW
Fon: +44 - 1 - 782 753 304
Fax: +44 - 1 - 782 753 377
info@johnsons-photopia.co.uk

Regards,

Jordan Miller

I have been frustrated spending weeks trying to get a medium format digital view camera system set up and working, but nobody seems to want to mount  Schneider Apo-digitar lenses onto Sinar P3 lensboards - whenever you ask someone for a price they reply with questions and not answers.

I have a Hasselblad H3D11-50, but what goes on the back of the camera should not effect mounting lenses on the the front of the camera, especially if you intend to slide and stitch and use all the image circle.

The P3 system is an open system so anyone can manufacturer P3 compatible lensboards ( or P3 lens board compatible cameras)... but I do not know if anyone does.

I understand that the separation of the elements is critical, and so you need shims to adjust for different thicknesses of lens panel and /or shutter... and if the thickness of the lens panel is not standardized, this might be a problem.

If you mount a Schneider lens on a Schneider electronic shutter you would hope that it should not be too complicated.

If you buy a new lens I imagine that you would get installation instructions and a set of shims... if you buy a second hand lens, you might not get the shims or the instructions and it might be difficult to mount the lens for optimum performance.

If you buy a lens mounted on a P3 lens board - how do you check that it is mounted correctly?

Schneider do not seem to have an official UK dealer.

I an an engineer, and I have a vernier caliper, and I hope to have several Schneider APO-digitar lenses, so I thought it might be worth climbing up the learning curve and doing it myself (as if there was not enough to learn).

Has anyone any relevant advice or information?

Dick Roadnight

[Joe Behar]

Have you read this? LL Thread - Joseph Holmes on MFD

GBPhoto,

If you meant that link for me, I don't really see the relevance. On a view camera, the only thing that matters is that the sensor and groundglass are on the same plane. Assuming this is true (notice I said "assuming") then as long as the lens is not askew on the lensboard, the actual thickness of the board is irrelavent.

[Dick Roadnight]

Dick,

Both Schneider Optics and Linos-Rodenstock offer their respective digital lenses, in a factory mounted configurations,

The second-hand market can prove to be tricky, when and if you do not have the ability to properly test, and evaluate the lens.

With regard to the proper mounting of a lens, you are forced to rely on the manufacturers abilities to properly assemble, mount, and calibrate the lens(es) in question.

I cannot speak directly for Schneider's representation in the UK, however the Schneider Kreuznach website provides the following contact information: JOHNSONS PHOTOPIA Ltd.

Regards, Jordan Miller Digital Technology Group, Inc.

Thank you for the information - my search of the web site revealed no UK Schneider Agent, I will contact them.

I contacted one of the Uk's best know suppliers about the purchase of a new apo-digitar 210mm, and they have been messing me about for days - on their web site they quote a price for the lens with an electronic shutter, but cannot (yet) give me a price for putting it on a lensboard, even though I have answered all their questions: they might, of course, have no stock and get lenses in to order from the manufacturer, or they might be (or might think they are) kitted up to mount them themselves.

This is the firm who has a Seitz specialist who told me that "no pictorial photographer would ever spend that much on a camera like that" without even asking me what I intended to do with it, or, presumably, realizing that the £14k digital bit can be used on several different cameras, including the digital roundshot.

I have a few apo-digitars and similar or equivalent lenses which I want mounting on P3 lensboards ( and electronic shutters).  

Dick Roadnight

[yaya]

Hello Dick,

JP are the official UK distributor for Schneider. You can also get very good advice from Paula Pell-Johnson at Linhof-Studio as they deal with lens re-mounting, servicing etc.

Another good contact is Andy Quiney at Peartree who also sell Schneider and Rodenstock lenses.

Yair

[Dick Roadnight]

Hello Dick,

JP are the official UK distributor for Schneider. You can also get very good advice from Paula Pell-Johnson at Linhof-Studio as they deal with lens re-mounting, servicing etc.

Another good contact is Andy Quiney at Peartree who also sell Schneider and Rodenstock lenses.

Yair

Thank you - I have been in contact with Paula, and I have bought an Apo-digitar from her. (yet to be mounted)

[Dick Roadnight]

Dick,
    Both Schneider Optics and Linos-Rodenstock offer their respective digital lenses, in a factory mounted configurations, including those to be used on the Sinar P-Series platform. Have you considered purchasing Schneider APO-Digitar lenses in this manor? With this configuration, Schneider procures the necessary Sinar-specific lens board and mounting components directly from Sinar AG.

Most all digital-specific lenses require a critical degree of precision in the mounting process, to maintain the necessary flange-focal distance and image field. This is especially true with those lenses that are 35mm in focal length or shorter.

Jordan Miller
Digital Technology Group, Inc.

I have now had a reply from Schneider, and they say that they no longer support the Sinar P3 system, as Sinar will not send them drawings (Sinar claim that the P3 system is an "open system").

With a large format (Sinar P) system you do not get an infinity mark, but Schneider say that have difficulty getting infinity focusing right, particularly with the shorter focal lengths.... presumably with the M & HY6 systems.

Schneider and Sinar people in the UK have said that I would have to sent the lenses away to Europe to me mounted, but Schneider say that I can easily mount the lens myself.

Hasselblad have changed their digiback mount, Sinar want everyone who wants MF digital view cameras to buy everything from them...

[Dick Roadnight]

I have today put the Schneider Apo-Digitar/Silvestri sliding stitching back/Sinar P3/Hasselblad 50Mpx DCU/Mac Book Pro system together and taken a photograph.

Everybody has discouraged me from persevering with MFD View cameras, and I can see why... but I hope it will allow me to take some marketable pictures.

[Dick Roadnight]

Dick,
Most all digital-specific lenses require a critical degree of precision in the mounting process, to maintain the necessary flange-focal distance and image field. This is especially true with those lenses that are 35mm in focal length or shorter.

The second-hand market can prove to be tricky, when and if you do not have the ability to properly test, and evaluate the lens.

With regard to the proper mounting of a lens, you are forced to rely on the manufacturers abilities to properly assemble, mount, and calibrate the lens(es) in question.

The 150 seems OK, but the 90 is extremely soft all over... and this lens has just had the shutter serviced and been mounted on a P3 lensboard.

If you buy a lens on E-bay, the vendor says it is OK and sharp, and you test it as soon as you get it, you have a chance of doing something about it... if you accumulate lenses over a period of months while getting the kit together to use them, you are in difficulty if they do not work, especially if some else has worked on them in the mean time.

I can check the lens/camera/adaptor/sliding back for focus errors by photographing a fence or power poles, if I can create conditions in which part of the image is sharp, that might be a start. Using kit from six manufacturers make it difficult to blame anyone.

I can examine the lens for loose elements, etc.

I can check the dimensions of the (press) shutter.

I can change the inter-element distance by partially unscrewing the lens... perhaps the manufacturers shims have been lost.

Has anyone got any other ideas?

[jimban]

The 150 seems OK, but the 90 is extremely soft all over... and this lens has just had the shutter serviced and been mounted on a P3 lensboard.

If you buy a lens on E-bay, the vendor says it is OK and sharp, and you test it as soon as you get it, you have a chance of doing something about it... if you accumulate lenses over a period of months while getting the kit together to use them, you are in difficulty if they do not work, especially if some else has worked on them in the mean time.

I can check the lens/camera/adaptor/sliding back for focus errors by photographing a fence or power poles, if I can create conditions in which part of the image is sharp, that might be a start. Using kit from six manufacturers make it difficult to blame anyone.

I can examine the lens for loose elements, etc.

I can check the dimensions of the (press) shutter.

I can change the inter-element distance by partially unscrewing the lens... perhaps the manufacturers shims have been lost.

Has anyone got any other ideas?

Hi Dick-

It sounds to me like the plane of sharp focus on the ground glass doesn't match the plane on the sensor.  Before trying to adjust the lens elements I'd try comparing a sequence of carefully focused shots such as the following:

Set the lens to it's fastest setting.

shot 1 - Focus the gg on a subject (like a tree) at 20 feet.
shot 2-  Focus past the subject by 0ne foot
shot 3-  Focus past the subject by 3 feet
shot 4-  Back off and focus in front of the subject the subject by 1 foot
shot 5-  Back off and focus in front of the subject the subject by 3 feet

If the focus doesn't match have the sliding back calibrated to your camera back.

jim

[Dick Roadnight]

Hi Dick-
It sounds to me like the plane of sharp focus on the ground glass doesn't match the plane on the sensor.  
jim

I think this is the place to start - image focus (depth of focus rather than depth of field) is more critical on shorter lenses, so this would explain the 90 mm being worse than the 150 mm.

... but it is easy to check it with a single exposure but photographing a fence, or power pole and cable, or a row of trees.

Getting technical, it is possible to use the formulae in Harold Merklinger's Book "Focusing the View Camera" to calculate the error in the position of the focusing screen.