Attempting to Replace Lens on Gowlandflex, Don't Know What I Need

[John Kasaian]

You could email Alice Gowland.
http://www.petergowland.com/PeterGowland_Contact.html
If she dosen't know the answer she could possibly link you to one of Peter's employees who might know. I don't remember hhis name but they was a fellow who worked for years with Peter building those cameras.

[ic-racer]

ic-racer, (or anyone), I'll expose my abilities here and ask, how do I check the collimation?

Curved lensboard--- Marizu has a good suggestion to try and find the exact same type of lens and shutter that was on there in the first place. Maybe Marizu can post a picture of his lens as a guide of what to look for. If you are unsure how collimation is done, you could send the camera and lenses to some one like Richard Ritter or SK Grimes.

Basically collimation involves setting the taking lens on the camera so that at infinity where parallel,( i.e. collimated) rays enter the lens they focus on the film. If the camera has a back stop (like a Rolleiflex) you would set the lenses based on that. Otherwise use 'infinity' as defined by the point on the focus scale when the viewing lens focuses collimated light on the viewing screen.
A convenient source of nearly collimated rays is light reflected or emitted from a distant object. Far away trees or mountain etc.

A practical test would be to take pictures of a distant scene with the taking lens wide open and bracket the focus. Take notes. If the sharpest image is the one exposed when the taking lens was in focus, then you are all set. If not, then adjustments to the lenses or the focusing screen placement are needed. Can you put a focusing screen on the taking lens part of the camera? You could check it that way, but should still test it with film to make sure.

More interesting reading here: http://www.monopix.co.uk/collimator.shtml

[ic-racer]

This is how I'd like to have it set up If I had it. Maybe SK Grimes can modify it similar to this this if you can't find the original type lens:

[jnantz]

You could email Alice Gowland.
http://www.petergowland.com/PeterGowland_Contact.html
If she dosen't know the answer she could possibly link you to one of Peter's employees who might know. I don't remember hhis name but they was a fellow who worked for years with Peter building those cameras.

+1

[JosephBurke]

I have the same Gowlandflex TLR and 210 lens combo. This is the earlier version. You can simply remove that panel/lens board holding the twin lens assembly. My viewing lens is a 210 Xenar like yours and the taking lens is a Schneider Symmar 210 5/6 in a COMPUR shutter.

[Oren Grad]

On his early 4x5 Gowlandflex TLRs, Peter generally used Xenar viewing lenses and Symmar taking lenses. I don't know whether that was because he had verified that the different designs matched *exactly* in FL, or because he tweaked the lens mounts so that focus was close enough in portrait range and he didn't care beyond that.

Something did change in his thinking, because I have a late-model Gowlandflex with a pair of 180 Sironar-N lenses in Copal 1.

I think the answer is that you can't assume that any particular taking lens will automatically match your viewing lens. If you want to be sure of accurate focus throughout the distance range, the simplest thing to do is probably to get two matching lenses - not a big deal these days, as excellent '80s-vintage 210 plasmats (e.g. Symmar-S, Sironar-N) tend to be very affordable now - and be prepared to shim the mounts relative to each other until focus matches.

[jbhalper]

Thanks again, to everyone who replied. I'll get in touch with Alice to see if I can find anything that way, and look into the Schneider Symmar 210 with a Compur in the meantime.

Thank you very much Joseph for confirming the lens on yours.

I'm not looking to make this happen overnight anyway, so I can be patient with the project.

[Oren Grad]

This discussion piqued my curiosity, so I checked the vintage lens data section on the Schneider Optics (US) website. FWIW and for future reference, the 210/4.5 Xenar is specified as having an actual focal length of 211mm and FFD of 201mm, while the 210/5.6 Symmar is specified as having an actual focal length of 212mm and FFD of 205mm.

[Marizu]

This is how I'd like to have it set up If I had it. Maybe SK Grimes can modify it similar to this this if you can't find the original type lens:

This is a different (later) camera.
The one that you showed has parallax correction, via front drop, on the taking lens. Ours are older ones and do not have this. I wondered whether the kinked lens board was some kind of rudimentary attempt to correct for parallax (but I can't think how). The taking and viewing lenses are at slightly different angles.That's why I say that he was doing some weird voodoo with this camera.

Also a correction to my earlier post... My lens is in a Compur shutter. The times are slow but it syncs with flash.
I can provide any specific pictures that anybody requires.

[jbhalper]

Oren, thanks for the measures from Schneider. I think I'm honing in on what will be my solution. I'm going to wait it out a little while to see if I hear back from Alice Gowland or anyone else before I pull the trigger.

And again, thanks all for giving me thoughtful, generous advice on my first post here. I really appreciate it.