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

[jbhalper]

I'm not quite sure what I need to provide to ask this question, but I'm looking for some help. I inherited a Gowlandflex TLR. From what little I've found so far, it looks like maybe an earlier model box-style one, with the rotating Graflok back.

The Schneider-Kreuzach Xenar 210mm viewing lens is still with the camera, but as you can see from the picture, the picture lens is missing. I don't know exactly what I'm looking for to attempt to rehab this camera, and was hoping I might be able to get some guidance from some more experienced, wiser photographers.

The opening on the lens board is right around 42mm across (the circle is not perfect, so it's between 41.6mm and 42mm), and it's slightly protruding so the outer limit of the plate that is flat is about 46mm across.

88857

I only started with large format in July or so, and I'm really not confident in my ability to pick out the right replacement here on the first try.

My thanks in advance for your time and attention!

[ic-racer]

Is this a 5x7 camera?
If I had that camera I'd look for a couple newish Symmar-S 210mm lenses that are multicoated. Those are plentiful on the on the used market and pretty inexpensive. You don't need a shutter on the top lens, but the Symmar-S lenses are usually so inexpensive the shutter is essentially free. Just leave it open. Therefore, I'd just make a new lensboard that is flat and forgo the complexity of trying to match the flange focal lengths of one lens 'in barrel' and the other 'in shutter.'

[Gem Singer]

Judging from pictures on the Peter Gowland website (www.petergowland.com), this could be an older 4x5 Gowlandflex camera.

Any standard 210mm lens, mounted in a Copal 1 shutter, from a major manufacturer, should work just fine. An older Schneider Xenar would be ideal.

Check with KEH (www.keh.com). They have one in stock.

[jnantz]

Judging from pictures on the Peter Gowland website (www.petergowland.com), this could be an older 4x5 Gowlandflex camera.

Any standard 210mm lens, mounted in a Copal 1 shutter, from a major manufacturer, should work just fine. An older Schneider Xenar would be ideal.

Check with KEH (www.keh.com). They have one in stock.

+1

enjoy your gowlandflex, they are wonderful ...


john

[jbhalper]

Yes, a 4x5, sorry for not including that originally.

A 210mm with a Copal 1, huh? Thanks for the guidance, I'll start looking around. Love KEH, thanks for the guidance.

[Marizu]

Mine is exactly the same as that but it has a vertical viewing 'chimney' with a magnifier in the top.
It has a 180mm Xenar viewing lens and a 180mm Symmar taking lens fitted.
I am guessing that this is because the Xenar is slightly faster (f4.5 vs f5.5).
The lens board has a small top hat bulge (like yours) for the taking lens which has something to do with the fitment.
I'd look for a 210mm Symmar if I were you.
My Symmar is an old one in a Copal shutter that has speed markings 1, 2, 5, 10, 25, 50, 100, 200, 400 but it syncs with flash nicely.
This is a really enjoyable camera. I love it!

[ic-racer]

Yes, a 4x5, sorry for not including that originally.

A 210mm with a Copal 1, huh? Thanks for the guidance, I'll start looking around. Love KEH, thanks for the guidance.



You can only use the exact same lens that was originally on that camera unless you make a new lensboard or go to great lengths to calibrate the flange-to-film distances of the existing lens in barrel to a different lens in shutter using shims on the mounting flange of one of the lenses.

Just look at the film-to-flange distances on the 210mm lenses listed here ( http://www.largeformatphotography.info/lenseslist.html ). No two are the same !!!

Marizu's advice seems sound (Find an older Symmar 210) but be sure to check the collimation of both lenses.

If it were me, I'd go with two identical modern multicoated Symmar-S lenses and a flat lensboard and leave the shutter on the top one open.

Using different lenses for the top and bottom is just asking for trouble. Peter did it correct the first time but now the lens is gone and so is Peter.

[Marizu]

Ic-racer, these cameras do not take a flat lens board. In addition to the top hat for the taking lens, the lens board has a bend in the centre!
I don't know exactly what the angle is but I recon it is about 5 degrees. The OP can check this by running their finger along the edge of the board from top to bottom.
Seriously, just getting a Symmar of similar vintage to the taking lens (check approx age by serial number) is the best way that I can think of to get this thing working right.

Peter Gowland was doing some weird voodoo with this camera.

[jbhalper]

Marizu is right about the lens board. The way that it is held in place is with a shallow bend that creates the tension so that it is secure. I would have to go to some trouble finding a large enough, strong enough piece of metal and then getting the holes and angle remade as well.

ic-racer, (or anyone), I'll expose my abilities here and ask, how do I check the collimation? Is that the film-2-flange measurement on the lens list there? I presume I want them to be exactly the same, or one at the flat measure of the board, and the other accounting for the approximately 1cm difference because of the way the stock film board is designed? I understand if you can't answer this part directly, but I appreciate your replies in general.

Does anyone know if the phone number at http://www.petergowland.com/camera/repairs/ is safe to call? I don't mind getting someone who doesn't know what I'm talking about, but I'd hate to upset someone by asking for Peter.

Having different lenses that don't work in tandem is not what I hoped for, but would be operable in some less than optimal way because the graflok back does have glass to focus against.

I do have the viewing hood (removed in the attached photo) and the real magic of this camera for me right now is simply looking through the focusing lens right now. Gorgeous.

[E. von Hoegh]

Marizu is right about the lens board. The way that it is held in place is with a shallow bend that creates the tension so that it is secure. I would have to go to some trouble finding a large enough, strong enough piece of metal and then getting the holes and angle remade as well.

ic-racer, (or anyone), I'll expose my abilities here and ask, how do I check the collimation? Is that the film-2-flange measurement on the lens list there? I presume I want them to be exactly the same, or one at the flat measure of the board, and the other accounting for the approximately 1cm difference because of the way the stock film board is designed? I understand if you can't answer this part directly, but I appreciate your replies in general.

Does anyone know if the phone number at http://www.petergowland.com/camera/repairs/ is safe to call? I don't mind getting someone who doesn't know what I'm talking about, but I'd hate to upset someone by asking for Peter.

Having different lenses that don't work in tandem is not what I hoped for, but would be operable in some less than optimal way because the graflok back does have glass to focus against.

I do have the viewing hood (removed in the attached photo) and the real magic of this camera for me right now is simply looking through the focusing lens right now. Gorgeous.

"Collimation" is the wrong word.
Ideally, both lenses would have the exact same focal length, so the viewing and focussing lenses would track properly- that is, you would shim one or both lenses so they are both at infinity focus, they will then have coincident focus down to the closest focussing distance allowed by the camera.

[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:
89028

[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.

[Don Dudenbostel]

The best solution but most expensive is to send your viewing lens to Schneider / Century Optical in California. They can measure your existing lens specs / FL and hand pick a matching new lens. Very good people to work with.

Second choice, KEH has a ton of Symmar S 210mm lenses. Order one and try it. If it's off order another and return the first. Explain what you're doing and keep trying. You might get one close enough for a couple hundred dollars. KEH has a very good return policy. At the most you're out a little postage.

It's true that the FL of each lens is slightly different but they may be close enough at the distance you'll be shooting.

[JosephBurke]

For what it's worth I wondered how exact the focus was calibrated (by Peter Gowland) was/is on my early 4x5 Gowlandflex. Since you can focus on both the top GG and the GG at the film plane they appeared reasonably spot on visually. In actual testing, if you call it that, with film (polaroid) with the lens wide open and a ruler at a 45 degree angle the focus on the GG up top and the resulting image confirmed that it is just that--spot on.
Regarding parallax correction, both my early model and the later version I have both have this feature.

[JosephBurke]

For the original poster, I think I would just find a Chrome rim 210 5,6 Symmar like Peter Gowland used in a Compur shutter, mount it, and do a similar test. That should do the trick.

[jbhalper]

Just coming back to update:

I bought a Symmar-S 210mm Lens with a Copal 1 shutter. Perfect fit for the lens board taking position.

Mounted the lens, had no problems getting a focus, but major problems getting it in sync with the viewing lens initially. There was about a 1cm difference.

Removed some felt added to the graflok back that looked legitimate, but confirmed that this brought everything closer together. Found that the bump on the original lens board in the picture was the remaining difference. I created a test lens board out of thick card-stock, without the bend or the bump and then both lenses came into focus simultaneously.

I found a local metal shop to copy my existing lens-board to an identical version without the bend or bump, and have installed everything with excellent results.

I'm fine-tuning things now, and may need to shim things up, and possibly to put that bend back in the board for some parallax correction, but I'm not sure that matters a lot. There's a clever sliding frame beneath the viewing glass that outlines the part of the frame which will be in use on the taking glass, and since I can see both, I'm confirming that it's pretty accurate as-is already.

Thanks again to everyone for the help. I'm quite close to a nicely functioning and restored Gowlandflex, and while it had a nice story before it was working, I'm happy to have a little more story of my own to add to it. Just going to test things out, possibly shim a lens, and then clean it up a bit.

[pierre506]

Congratulations～

[Steve Smith]

Since you can focus on both the top GG and the GG at the film plane they appeared reasonably spot on visually.

If you can do that, it would be easy to shim one of the lenses to make them match. If this was mine, I would just get a lens and try it then see where to go from there.


Steve.