Linhof Technikardan film registration

[frank_doering]

I am having film registration problems with a Linhof

Technikardan 45S that I suspect will be widely shared.

Calculations based on careful test shots, as well as

measurements with a homemade rig, concur in the conclusion

that sheet film in Fidelity holders comes to sit about 0.5 mm

behind the plane of the groundglass. The discrepancy is too

large to be chalked up to measurement error. The camera back

was inspected by HP in NJ and Linhof in Munich and found to

meet their specifications. So I suspect there is a mismatch

between Linhof specifications and Fidelity dimensions. Btw, no

such discrepancy exists in my Linhof Kardan GT 810. Any

suggestions as how to get this fixed?

[thomas_vaehrmann]

Frank,

 

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I don't know or own the Technikardan, but on my older Technika there

are some small distance-plates to adjust the position of the

groundglas. If you can measure exact, check this out and try to move

the groundglass 0.5 mm back to match the film. Did you measure with a

film sheet inside the holder?

[bob_salomon]

Linhof;s ground glass rests on shims to adjust the position of

the film plane by service.

 

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Normally this is done by adjusting to a factory recommended

position. But the question is have you used this holder to shoot

film and find it less then sharo or are you doing a series of

meansurements prior to shooting?

 

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If so shoot film first.

 

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Have you sent the camera to Marflex or just called them?

[michael_kadillak3]

Have you eliminated the film holder from the equation? Does it meet

factory specs across the entire surface area?

[michael_briggs2]

I have carefully tested the focus of my Technikardan 45S and it is

correct. It seems very unlikely that film registration problems "will

be widely shared" on a camera that has been sold for almost a decade

(the "S" version) and used by numerous experience photographers.

 

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If it were true that the film plane lies 0.5 mm behind the ground

glass plane, this is easily fixed by adding shims in front of the

ground glass (the other direction would be harder to fix). My

suggestion: carefully focus the camera and take a test photograph of

an object with fine detail. Using a fairly close object will give you

a small depth of field to make the test more stringent. Place a label

on the object being photographed so that there will be zero chance of

being confused about which film is which. Remove the screws that hold

the ground glass in place and add shims totaling 0.5 mm on top of the

existing metal shims. For temporary shims, you can use one or more

pieces of cardboard or masking tape. Replace the ground glass and

screws, change the label on the object, refocus and take another

photo. Examine the negatives to see which is in better focus.

[jorge_gasteazoro]

I dont know Frank I have had my TK45 for 10 years.....the only times

I got images out of focus it was my fault. (wrong movement, not

paying attention, etc). I think maybe it was your holder that was

faulty. Try it with a different holder from a different manufacturer

and see what the results are.

[bob_salomon]

Strange that Frank doen't anser any of the questions raised or

the suggetions.

 

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Why not Frank?

 

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I checked with Krikor at Marflex today and he was not familiar

with this so some feedback would help.

[jim_brick]

I have been using a TK45S for many years and have never had out of

focus photographs other than when it was my own fault. I use a Fuji

Quickload holder and Quickload film for color. I use Grafmatic

holders for B&W. I replaced my standard ground glass screen with a

Boss screen a couple of years ago. It made a lot of difference for

me. Critical focusing is really easy with the Boss. I make prints

between 30"x40" and 48"x60" and if I had a focus problem, it

certainly would be evident.

 

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Jim

[frank_doering]

Sorry for not getting on the thread any earlier; I'm having

connectivity problems. Thanks for all the suggestions.

 

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I think I have found the cause of the problem. The fabric that's

used as a lighttrap on the camera back seems to be a little in the

way. It is fully compressed by the groundglass frame, so that the

frame sits flush with the back. But it isn't fully compressed by the

film holder (which has a wider rim than the groundglass frame

and therefore, I presume, exerts less pressure per square in on

the fabric). As a result, the film holder comes to sit a little further

back than it should. One can actually see a small gap, which can

be closed by pressing on the back from behind.

 

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Frank