View Full Version : Mounting a lens on a Gowlandflex
I recently bought a beautiful 1929 Heliar lens after years of searching in the hopes that I could swap it with the Schneider mounted on my Gowlandflex. The local store quoted me 500 EUR (650 USD) which sounds like highway robbery to me, even by European standards. They recently charged me well over 200 EUR to fix a PC port I broke on the same camera while tripping over a cable, which was painful enough.
The lens didn't come with a lens board, but was mounted in a probably similarly aged but working Compur shutter. I would have preferred to use my current Copal shutter, and just swap the lens, but apparently its threading is different. So they would have to build a new lens board to mount it. And that plus work ends up costing more than the lens itself.
Now, perhaps a more prudent approach is to get the lens and shutter CLAd, and doing the rest myself. Is finding a lens board suitable for the Heliar and Gowlandflex, mounting and adjusting something that's ill-advised as a DIY project? The focal length remains the same, but I would likely have to adjust focus to ensure it is accurate.
Below how the lens came.
84971
E. von Hoegh
8-Dec-2012, 08:51
Mounting that lens on a twin-lens reflex is more of a task than you think, and may well be impossible. The problem is that the nominal focal lengths are the same, but the actual focal lengths may differ. If the actual focal length of the Heliar is different from the viewing lens, the lenses will not track properly. Even if they are identical, there will need to be a compensation made for a probable difference in flange focal length, i.e. the distance between the rear surface of the shutter (where it contacts the lensboard) and the filmplane.
Joseph Dickerson
8-Dec-2012, 09:20
Mounting that lens on a twin-lens reflex is more of a task than you think, and may well be impossible. The problem is that the nominal focal lengths are the same, but the actual focal lengths may differ. If the actual focal length of the Heliar is different from the viewing lens, the lenses will not track properly. Even if they are identical, there will need to be a compensation made for a probable difference in flange focal length, i.e. the distance between the rear surface of the shutter (where it contacts the lensboard) and the filmplane.
I'm betting the Gowlandflex is an SLR not a TLR.
JD
E. von Hoegh
8-Dec-2012, 09:37
I'm betting you'd lose. http://www.google.com/imgres?q=gowlandflex&num=10&hl=en&safe=active&tbo=d&biw=1280&bih=906&tbm=isch&tbnid=jBFv4GloBhSNjM:&imgrefurl=http://www.petergowland.com/camera/&docid=N5A3iQqzboplIM&imgurl=http://www.petergowland.com/camera/CameraPageImages/WideAngleGFlex.jpg&w=319&h=392&ei=wGzDUMbzCeLh0gH77oHQBw&zoom=1&iact=hc&vpx=256&vpy=408&dur=8325&hovh=249&hovw=202&tx=93&ty=144&sig=113451129022196617669&page=1&tbnh=153&tbnw=125&start=0&ndsp=45&ved=1t:429,r:22,s:0,i:156
I'm betting the Gowlandflex is an SLR not a TLR.
You'd lose that bet.
E., I'm aware of the nominal vs actual focal length difference, but I'm not too worried about that. I use the camera at camera-to-subject distances which vary very little (sitting or full length people (http://www.largeformatphotography.info/forum/showthread.php?97693-Gowlandflex-pinups&p=963901&viewfull=1#post963901)) and at small-ish apertures (f16-f22), so that shouldn't be a major factor.
I found the lens board specs from another post (http://www.largeformatphotography.info/forum/showthread.php?17650-Gowland-Lensboard-Specs-Anyone&p=160471&viewfull=1#post160471). Mr Gowland sold lens boards, and I contacted Mrs Gowland in case he left stocks. If she doesn't, then I'll have to make my own. I'd still have to figure out how to mount the lens to the board, and the board to the camera, and to adjust focus for the sweet spot. And I don't know if that's something that's doable for an inexperienced DIY with time to spare, or whether I should splurge (yet again) on a pro to do the job for me.
E. von Hoegh
8-Dec-2012, 10:33
You'd lose that bet.
E., I'm aware of the nominal vs actual focal length difference, but I'm not too worried about that. I use the camera at camera-to-subject distances which vary very little (sitting or full length people) and at wide-ish apertures (f16-f22), so that shouldn't be a major factor.
I found the lens board specs from another post (http://www.largeformatphotography.info/forum/showthread.php?17650-Gowland-Lensboard-Specs-Anyone&p=160471&viewfull=1#post160471). Mr Gowland sold lens boards, and I contacted Mrs Gowland in case he left stocks. If she doesn't, then I'll have to make my own. I'd still have to figure out how to mount the lens to the board, and the board to the camera, and to adjust focus for the sweet spot. And I don't know if that's something that's doable for an inexperienced DIY with time to spare, or whether I should splurge (yet again) on a pro to do the job for me.
OK, for one distance you can make it work (and the focal lengths may be close enough that it will work at all distances) . You'll need a lensboard with the proper size hole - which should not be expensive - and some way to shim the lens if neccesary. I don't know what your skill set or your tool set is like, but any metal worker would be able to cut the hole in the new board. What are the dimensions of the board? Is it a simple flat board?
edit - just read the specs in the link. That's an easy board to make, if neccesary.
Joseph Dickerson
10-Dec-2012, 09:06
Wouldn't be the first bet that I've lost, but Peter did make SLRs as well as the TLRs (TLRs are much more common though).
Just setting the record straight...:rolleyes:
JD
E. von Hoegh
10-Dec-2012, 09:22
Wouldn't be the first bet that I've lost, but Peter did make SLRs as well as the TLRs (TLRs are much more common though).
Just setting the record straight...:rolleyes:
JD
IIRC the Gowland SLR used one lens only, a 240.
JosephBurke
10-Dec-2012, 09:38
Gowlandflex? You want one...I have a pair....I don't need two. Serial #508 or similar IIRC..... One of the earlier TLR's with the rotating back. 210 mm lenses (Symmar conv.)
E. von Hoegh
10-Dec-2012, 09:40
Gowlandflex? You want one...I have a pair....I don't need two. Serial #508 or similar IIRC..... One of the earlier TLR's with the rotating back. 210 mm lenses (Symmar conv.)
I'd love to have one, a useable piece of photographic history. Unfortunately, I cannot afford one. Dammit.
I think making the lens board is the easy part...
Any idea how I could remove the lens board from the Heliar lens/shutter assembly? Pictured below, it is the square metal piece, along with the silver ring attached to it. It rotates freely, and there are no screws that are clearly keeping it in place.
There's not enough room in the existing lens board hole to bring the Heliar lens assembly into place from the rear, so I would have to remove the lens board to figure out what my options are going forward.
An alternative solution I considered is to just mount the lens as is (below) to the front of the existing lens board, and it would work. The only "minor" issue is that it brings the image plane too forward, so I wouldn't be able to focus at ranges I need to (3-5 meters).
Heliar lens:
84971
Gowlandflex without a taking lens:
92284
I finally figured out at an always helpful local camera shop that there was a retaining ring in a deep recess, which I was able to unscrew without a spanner wrench, which didn't reach deep enough. The lens was then separated from the lens board (pictured on the left). I did the same with my old lens (middle) with a spanner wrench, and now I have a round aluminum lens board which fits the Gowlandflex (right). It mounts to the camera using threads on the outside edge of the lens board, and the lens itself is held in place only by the retaining ring.
The only problem is that the board doesn't fit the Heliar - it has slightly wider barrel. I've been to two metal shops, and they can't widen the hole because they don't have big enough of a drill bit (!), and they didn't warm up to the idea of grinding it. Using some kind of grinder on my drill appears to be ill-advised on aluminum. Something about explosions and fire :eek: Looks like I'll have to widen it by filing it away with a metal file.
Fortunately it doesn't have to be exact, as no threading is needed on the inside edge of the lens board. So I should be ok as long as I file the hole large enough to fit the Heliar, but small enough so there are no light leaks around the retaining ring.
You probably knew all this already, but I'm recording this for posterity for those working on Gowlandflexes in the future.
Anything I'm missing? Does anyone have experience with filing 2mm thick aluminum lens board; the widening needed is 2-3mm? Will I be spending a whole day on this? Any tips?
93996
If you can get something like this
http://www.globalindustrial.ca/p/tools/abrasives/abrasive-flap-wheels/3x1x1-4-20-alum-oxide120-grit-flap-wheel?gclid=COGotvGG5LYCFUNgMgodyAkADw
You can enlarge the hole carefully
Gundlach
25-Apr-2013, 04:47
This is a simple job for a machine shop, all that is required is a milling machine and a rotary table or mounted on a lathe and bored.
Gundlach
25-Apr-2013, 04:49
Aluminum does not grind well because it clogs the grinding stone immediately as the metal is so soft.
This is a simple job for a machine shop, all that is required is a milling machine and a rotary table or mounted on a lathe and bored.
That's what I figured as well, but I got blank stares at two shops.
Took about an hour with a file. Lens fit perfectly on the lens board, and so did the board on the camera. Eyeballing focus on the rear screen seemed to be spot on.
Tested with instant film, and had some atrocious light leaks. Took a few shots, until I noticed there was a screw hole on the board the lens board mounts to - probably to hold the original lens in place. Covered with gaffer tape on both sides, and the polaroids looked great and in focus, aligned with the viewing lens. Whew.
PC port is a bit temperamental as I have to push gently down on it for it to work, but when it fires it does so on time.
Studio tests tomorrow!
Studio shoot went well. PC port kept being flaky, thankfully my lights didn't break and I didn't get a single bad exposure due to it. I'll have it checked as part of a CLA.
I developed the slides, and they look great :D Dropping off the keepers to be drum scanned later.
Here detached lens, modified lens board, and retaining ring.
94824
And the Heliar attached to Gowlandflex:
Otto Seaman
10-May-2013, 10:51
That little Arcatech head is awfully cute underneath that monster... reminds me of Atlas lifting the world.
You need a better camera technician, it may be worth to send it out of the country. Even the most expensive US repair person wouldn't be close to those prices and they would do it right.
That little Arcatech head is awfully cute underneath that monster... reminds me of Atlas lifting the world.
I know, and it's not the smallest of ballheads... I bought it for my 6x6 TLR, but it works fine with the Gowlandlfex. In the studio I use a big honking tower stand.
You need a better camera technician, it may be worth to send it out of the country. Even the most expensive US repair person wouldn't be close to those prices and they would do it right.
Fortunately all I need now is a CLA (mostly L), and to check if he can do something with the PC port to make it more reliable. But yeah, everything is expensive in Europe.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.