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Fragomeni
11-Jan-2011, 23:43
Hi all. I'm currently working on a 20x24 restoration that you may have seen me mention in other threads. Richard Ritter is making a new ground glass back for the camera and I should have a 20x24 film holder on the way when the back is finished. Now 20x24 is big and it leaves room for a lot of smaller (but still big) sizes to be used within it. I'm curious if there are any ways that I can use smaller film sizes in my 20x24 film holder. I can easily make a mask for the ground glass for accurate composition but I'm stumped as to how I can place a smaller piece of film in the holder and keep it centered so that it matches the unmasked area on the ground glass. In interested in working with 16x20 and 12x20 in addition to the full 20x24. Someone must have figured out a way to do this so I'm hoping they'll chime in. and yes obviously I could have a reducing back and smaller holders made but clearly I'm trying to avoid that because that would be very expensive on top of an already expensive restoration project and I am a working artist so money is sparse. Thank you!

Brian C. Miller
12-Jan-2011, 00:02
Sure, use a custom film holder. Now, would the custom holder be less expensive than a reducing back? If you can fabricate a reducing back from a donor camera, then it really won't be expensive at all. You could get an old Orbit and use the back from that.

Fragomeni
12-Jan-2011, 00:13
The cheapest route would be to figure out a way to use the film holder I'll already have i.e. make a temporary modification or use some method of centering and holding the smaller film in the center of the holder. Just can't figure out how.

Fragomeni
12-Jan-2011, 00:27
My intention with this is geared toward paper negatives so I suppose I could just put the paper in the holder under safelight and use a low-tac tape (as to not leave residue in the holder) to tape down the edges of the paper not held in place by the film holder. I could then make the ground glass mask centered on the corresponding corner of the glass instead of centered in the middle of it. Crude but in theory it should work fine. Any other ideas?

Steven Tribe
12-Jan-2011, 02:22
I have found lots of plate/film holders were the owners have made temporary spacers and attachments for format reduction - none of them very good. There was an early patent with thin wood frames and thin sliding catches that are sometimes on sale. These are usually in sets. 10x8 down to 1/1 plate, then down to 5x7 etc. I have never seen them above 10x8, though. If you are handy you could make a set to reduce the negative size used. It would be best to use metal film sheaths to "round off" the reduction. It is MUCH easier than making a complete film holder - you can use readily available thin wood strips or plastic. The system shown reduces 13x18cm to 1/2 plate size.
This is basically a system for plate holders so some development of the idea is necessary for a dedicated film holder.

Drew Bedo
12-Jan-2011, 05:31
Francisco: I like Steven’s idea for an insert...Maybe something could be made using 20x24 film stock? Each sheet is expensive for film but would be easy to work with, would use the 20x24 holder without modification and so on. The cost would not be exorbitant compared to other materials, and you already have a sheet or two in hand.

I envision a 20x24 sheet cut with a winsdowthe size of the film to be exposed. Another sheet of 20x24 film with a window slightly smaller than the film to be exposed would be laminated over the first . . .a little like a mat for a frame.

Whatever you do, the problem will be flatness. In the end, it may be that tapeing the film directly to the holder works best for film flatness.

jb7
12-Jan-2011, 05:59
I think the low tack tape is the best idea-
you can make a mask from light card-
cut an aperture the same size as your film, and insert that in your holder, using double sided tape around the opening to stick it to the septum.

It should be quite easy to locate the position of the opening in the dark, by touch-

I'm working on a similar project, though I'm months away from having anything to show-

RichardRitter
12-Jan-2011, 06:55
Make a spacer that fits into one corner that has two legs. In the dark place into a corner slide film against it and tape film into place, remove the spacer and tape that corner.

By using a spacer and centering the film you can tape any size you want onto a back all the way down to 4 x 5. To tell were the film is on the ground glass use black(white) board markers on the ground glass on the outside surface to mark out a frame where the film is sitting. When done you can remove the marked reference frame.

Great way for testing film. Take a large sheet of film and cut it up.

Fragomeni
12-Jan-2011, 09:59
Make a spacer that fits into one corner that has two legs. In the dark place into a corner slide film against it and tape film into place, remove the spacer and tape that corner.

By using a spacer and centering the film you can tape any size you want onto a back all the way down to 4 x 5. To tell were the film is on the ground glass use black(white) board markers on the ground glass on the outside surface to mark out a frame where the film is sitting. When done you can remove the marked reference frame.

Great way for testing film. Take a large sheet of film and cut it up.

Thats the simple solution I was looking for! Thank you as usual Richard!

I knew there had to be a simple solution for centering the film in a larger holder. Its often the most simple ideas that fly under the radar because they're just so simple.

Thank you everyone for chiming in!

rguinter
12-Jan-2011, 10:25
Francisco: I like Steven’s idea for an insert...Maybe something could be made using 20x24 film stock? Each sheet is expensive for film but would be easy to work with, would use the 20x24 holder without modification and so on. The cost would not be exorbitant compared to other materials, and you already have a sheet or two in hand...

I see a lot of threads here in this forum by those who are using x-ray film.

I'm thinking if you wanted to go with the insert idea mentioned above using film stock, maybe you could ask someone in the forum to donate (or sell) you a couple sheets of x-ray film. You could cut it up for whatever size inserts you needed.

I uderstand the film is very cheap.

Just a thought. Bob G.