Author Topic: Help with a golden oldie . . . please  (Read 1297 times)

Alan

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Help with a golden oldie . . . please
« on: October 19, 2010, 09:47:42 AM »
Last week I received in the post a lovely TLR .  .  .

Its a Weltaflex from the mid 50's, info here > http://www.camerapedia.org/wiki/Weltaflex

Image taken from Camerapedia >



Everything works as they should except for the focusing, for some
reason I cannot acheive infinity focus or any focus I suspect.

Here are the results from the second roll of test film at different apertures.

Can anyone shed some light on the issue?

I received a full refund from the seller and he let me keep the camera also
he suspects a dodgy lens.


Skorj

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Re: Help with a golden oldie . . . please
« Reply #1 on: October 19, 2010, 10:11:34 AM »
Looks like a miscalibration of the lens focusing mech to me. Assume turning the focus knob on the left advances the bed out as you focus in (closer to the camera)? If so, infinity should be fully withdrawn? If not, that might be your issue.

If so (fully withdrawing) and still out of focus, then I would suspect a mis-aligned lens element? I have to ask, is the focus on the screen OK, and just the taking lens is kaput?

The tracing paper and candle trick might help if you can find a mechanical problem to fix before you waste any more film.

Also, damn nice looking machine regardless! Skj.
« Last Edit: October 19, 2010, 10:13:36 AM by Skorj »

Alan

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Re: Help with a golden oldie . . . please
« Reply #2 on: October 19, 2010, 01:54:29 PM »
thanks skorj,

i have tried placing some tracing paper at the film plane
and turning the focus adjustment makes little adjustment.

you are right, fully withdrawn is infinity so there is no
more adjustment available.

The lens is a simple triplet which is easy to demount.
The front 'element' screws off and the rear element screws off
and they look ok.

The viewing lens can be 'calibrated' easily to the infinity scale

I have tried swapping the taking with the viewing lens and it made
no difference.

I wonder if there is or should be 2 glass elements in the lens unit
on front of the shutter, its just 1 unit ?

I have tried unscrewing the lens at various stages but I suspect the
lens needs to be closer to the film plane . . . frustration  ???

Francois

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Re: Help with a golden oldie . . . please
« Reply #3 on: October 19, 2010, 04:28:38 PM »
Could simply be that the groundglass is not positioned properly. Some cameras (like the Mamiya C220/330) have shims under the glass to adjust focus.

Could also be that the glass was removed to clean and re-inserted the wrong way around (like I once did on my Graflex)
Francois

Film is the vinyl record of photography.

Alan

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Re: Help with a golden oldie . . . please
« Reply #4 on: October 19, 2010, 08:52:33 PM »
hi francois,

thanks for replying but even without using the viewing lens and using
some tracing paper on the film plane to look through with the back off
I cannot get focus.

I gan calibrate the viewing lens to infinity no problem.

Terry

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Re: Help with a golden oldie . . . please
« Reply #5 on: October 19, 2010, 10:43:27 PM »
A mount problem perhaps?  Maybe someone took the taking lens off and lost some shims or otherwise remounted it incorrectly.  Also, what's the linkage between the viewing and taking lenses?  (I don't know the Weltaflex at all, but there must be a geared linkage of some sort.)  Maybe said person disassembled the lens linkage and got it wrong. 

Francois

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Re: Help with a golden oldie . . . please
« Reply #6 on: October 19, 2010, 10:50:50 PM »
If infinity focus isn't achieved when the button is turned to infinity and the lens carriage is fully collapsed, then the focusing lens is off focus. Adjust this one first. Usually, the lenses are held with a ring and it's possible that the lens assembly is not seated properly.

Here's a great article of measuring focus
http://www.kyphoto.com/classics/collimator.html
Francois

Film is the vinyl record of photography.