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View Full Version : Graflex Curtain Shutter to Canham (SINAR) lensboard



Kimberly Anderson
29-Mar-2013, 06:33
Well a 3 1/4 x 4 1/4 Speed Graphic showed up yesterday. I sought out a non-perfect example and got this one for 99 bucks. The only thing that is remotely interesting about it is that it is engraved 'TVA - xxxxx' so there is some sort of tenuous connection to that part of US history.

The end-game with this camera is to take the shutter assembly and make a lens-board out of it. I have a few barrel lenses that I'd like to try to use with a shutter, and this option gives me a variety of controllable speeds. I have a Packard shutter already and have futzed with it for the past year or so and I know the benefits and downfalls of that shutter. It will be for sale soon and yes, it does work.

This particular Speed Graphic will also be parted out, so if you need little fiddly-bits for yours, let me know. I might keep the lens for my RB Auto Graphlex.

I did a quick look last night and the front standard of the Canham will be large enough for the SG shutter back to clear the standards and not interfere with the 'normal' operation of the camera. The shutter curtain dimensions are slightly smaller in the short dimension than the largest lens element I wish to use with it. I am wondering if it will vignette when shooting 8x10. I am thinking it probably will. 5x8 will more than likely be fine.

This morning I will begin stripping the SG and taking some photos and measurements.

I know at least one of you has been down this road, so if you have any suggestions, please pass them along. Yes I realize that I am potentially creating a cantilevered nightmare and am planning accordingly.

This project, in the end, might just be completely aborted, but part of me wants to see if I can make it work instead of just wondering 'what if'.

:)

jcoldslabs
29-Mar-2013, 13:52
I'll just chime in and say that I have a 4x5 Speed Graphic carcass with the shutter intact that I have been meaning to make into something I can use with my own barrel lenses, preferably on the Century 10A. I'm curious about other people's experiences as well. So far I've managed to find this (http://4.bp.blogspot.com/_fKXlhnDTeys/TO8dECgt5RI/AAAAAAAAB50/V7Xiz2SCIvo/s1600/SGshutter1.jpg).

My plan so far is to make a flexible (fabric? old bellows?) coupling between the Speed graphic and the front of the lens and mount the SG on a separate tripod. This will work fine in the studio but not so much in the field.

Jonathan

jp
29-Mar-2013, 18:19
http://www.largeformatphotography.info/forum/showthread.php?81042-someone-talk-me-out-of-this/page4&highlight=sigmar

http://jason.philbrook.us/~jp/scans/2012/sigmaroutside2.jpg

http://jason.philbrook.us/~jp/scans/2012/sigmaroutdoors.jpg

jcoldslabs
29-Mar-2013, 19:37
Nice, jp. Do you have any close-up photos that show the way you mounted it both to the lens and the camera? That's my biggest issue. The shutter tensioning knob and release trigger have to remain accessible which limits the kind of surround one can build to mount the shutter. I'd love to embed the SG into a lens board, but that won't work without burying the knob.

And what lens is that? Good lord!

Jonathan

Kimberly Anderson
29-Mar-2013, 19:38
Sweet. My setup will be a little more compact, but the idea is the same. Thanks for the pics. I'd love some detail shots. The link to the other thread is also helpful. :)

jp
30-Mar-2013, 04:13
I'll get some closeups today. Basically the camera body is compressed between two 9x9 lensboards. Someone may see the closups and figure out a more compact way and that'd be great too.

jp
30-Mar-2013, 16:38
OK, a six minute overview in 1080p.

https://www.youtube.com/watch?v=pAjyYixKXm8

jcoldslabs
30-Mar-2013, 17:04
OK, a six minute overview in 1080p.

That's really helpful, at least to me. Thanks.

Jonathan

Kimberly Anderson
30-Mar-2013, 21:22
Sweet, thanks for that Jason. I will probably do mine a little differently, but this gives me a great place to start. Can you address possibly in the future how the shutter speeds are? Are they accurate? Someone on LFF mentioned that they would probably not be. Thanks again!

jp
31-Mar-2013, 04:41
I haven't tested shutter speeds scientifically. I have shot film and it comes out properly exposed.

Glad the video is helpful; hopefully if someone else does something related, they can share their results too!

Jim Jones
31-Mar-2013, 07:59
While a SG shutter mounted just behind or in front of a lens will give exposures as expected from the selected shutter speed, it might not stop motion as much as the same shutter used near the film plane. This is because the slit in the shutter scans across the entire exit or entrance pupil of the lens, and the slit's transit time in a large old shutter like the SG is fairly slow. At very small lens apertures the exit or entrance pupil is small, motion stopping ability will approach that of the shutter mounted near the film plane.

Kimberly Anderson
31-Mar-2013, 09:54
Good to know Jim. Thank you.

Kimberly Anderson
31-Mar-2013, 10:43
I've been thinking about the weight issues involved with adding yet another large piece of equipment in front of the front standard on my Canham 8x10. I am strongly tempted to work out a solution where it sits behind the front standard. I see another additional benefit of putting it behind the front standard - I have at least one lens where the rear element protrudes backwards past the lensboard. Having the shutter assy. behind the front standard will buy me at least 1/2 inch of space.

I have a SINAR front standard at my disposal and will be taking it apart on Tuesday to see how it can best serve me in this endeavor. I will be stripping the remainder of the leatherette and sanding down the box today. Does anyone know what wood was used on these Speed Graphics?

Yes, pics will be forthcoming. Probably a short video too. The one previously posted has been very informative.

jp
31-Mar-2013, 14:32
The problem with with putting the speed graphic behind the front standard is either one of these.

1. Recess it (like a packard or other pneumatic), and you won't have access to wind it up, view shutter speed settings, or trip the shutter.

2. Perhaps canham is better engineered in this regard, but I can't remove the bellows from the front standard easily on my B&J, so I can't just move everything back a couple inches. If I could, it would make sense to do so.

My solution to lenses with protruding rear elements was to make my speed graphic assembly 100% reversible. If I rotate the assembly 180 degrees (around it's z axis), there would be about 3" of room for rear elements (as the curtain would be recessed) and the only difference would be the controls are on the other side of the camera.

Kimberly Anderson
31-Mar-2013, 15:28
The Canham is quite remarkable in that it is nearly as modular as the SINAR system. The bellows are easily detached from the front standard with one simple sliding tab. It would be no trouble to remove the front bellows, install the 'shutter/camera' and attach the bellows to the back of the camera if I design it to accept a standard SINAR bellows (which is my intent). The front standard of the Canham gives me plenty of clearance for the shutter/camera to mount on either side. Since I have the ability to decide either front or back, I am going to see if I can't go with the back of the standard. Pics are in order clearly.

Kimberly Anderson
2-Apr-2013, 07:29
Here's a shot of the box stripped of all parts and just kind of seeing how far back I need to place the shutter. This particular lens sticks out the furthest, so it's the one I'm basically making my distance decisions for.

This photo will basically give you guys an idea what I have to work with. The decisions and choices are pretty wide open at this point.

92529

Kimberly Anderson
4-Apr-2013, 08:02
I took the SINAR front standard and looked at my options with it. Unfortunately the bellows for the Canham camera do not share any dimensions with the SINAR system...so, my front standard and bellows are not usable for this project. I will be selling them. I was really, REALLY hoping to be able to use them, alas, I cannot.

I sanded down the Brazilian Mahogany of the Speed Graphic and gave it a light coat of Teak oil. The wood is very lovely and will look nice when I give it a clear coat when finished.

So, my plan moving forward is to mount the shutter box rear of the front standard, make a plate that receives the front of the Canham bellows, make a plate that will fit into the Canham front standard, mount those plates to the Graphex shutter box and reinstall the shutter assy. I am considering using the hardware from the front standard of the Speed Graphic to use as the mounting hardware for the bellows to the shutter box. I will re-use the lensboard sliders from the Speed Graphic on the rear of the shutter box. They are beefy and over-built and will be perfect.

Here are some measurements, kind of as an FYI, but this is a convenient place to put my notes.

Front mounting flange of Canham bellows: 6x6 inches
Rear mounting face of Canham front standard: 6x6 inches
Box dimensions of 3 1/4 x 4 1/4 Speed Graphic camera 5 5/8 x 6 3/8

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