Cutting down 8x10 sheet film for 5x7

[ed_brock2]

I'm looking for more emulsion options than are offered in 5x7. Are

there any inherent problems in cutting down 8x10? I think I could

notch the sheets (every other one) with a paper punch and cut them

down easily using a paper cutter with a taped guide. Will labs

accept sheet film which they cannot identify via notches? Will the

10" dimension of 8x10 film fit 5x7 holders when cut in half or is

there anything weird going on with sheet film dimensiions?

[john_shriver]

For sizes, there may well be issues. All the sheet film sizes are nominal sizes. The only true sizes were the glass plate sizes. The film sizes are smaller by a margin that allows the film to fit in a film sheath with the outside dimensions of the glass plates. The film sheath has bent-around edges that hold the film, so the sheet film is smaller than the glass plate.

 

The problem with cutting down that 10" length to 5" is that you may have to make one cut of just one or two millimeters, and that is tough with a paper cutter under any conditions, but particularly with something as stiff as sheet film stock.

 

I cut down 5x7 or 8x10 film to 3.25" x 5.5" size (3A size), and I do use a paper cutter with a taped on stop. I set the stop with a brass template I made, which is the correct size for my Kodak film sheaths. Obviously, you could use a real sheet of 5x7 film as a template.

 

Unfortunately, I can't measure the 10" size for you, since I can't read a ruler in the dark... (Unless one of my cut-offs is 10" long.)

 

It is a lot easier to mark the upper right corner by just chipping off that corner with the paper cutter. Trying to punch half a hole with a hole punch would be a pain in the butt. (Although that was my first thought as well!)

 

As for the lab, I suppose that depends. If they trust you. They could always nip off a small corner in the dark, and look at it. Unexposed B&W film looks very different from color emulsions. That is what they are worried about, B&W in a color line.

[alan_davenport2]

Ed,

 

John is right in that all film sizes are nominal. Since my prefered film(tri-x)is no longer available in the 5x7 size I must cut 8x10 films down. And because the actual size of 5x7 is 4 7/8" x 6 7/8" you cannot simply cut 8x10 film in half.

 

I use a Rototrim cutter and a plastic draftman's square to cut the film down. This requires cutting each batch of film twice, once for the long side(7") and the second for the short side(5"). This also requires re-adjusting the square between cuts. This I do by putting the cut film back into the box, moving the square and making the second cut.

 

A.B. Davenport

[michael_beckmann]

Have you considered using 13x18cm film? There are many options for 13x18 film from Kodak, Fuji, Agfa and Ilford. I guess with a different holder, you could use it in your camera unmodified.

[sal_santamaura]

5x7 Tri-x is in stock at Badger:<p>

 

<a href="http://www.badgergraphic.com/search_product2.asp?x=3655">320TXP<a/a>

 

<p>No need to cut down 8x10.

[michael_beckmann]

He said he wanted *more* emulsion options.

[sal_santamaura]

Michael, I was responding to Alan who said:

 

"Since my prefered film(tri-x)is no longer available in the 5x7 size I must cut 8x10 films down."

[john_shriver]

OK, the first cut I made cutting down 8x10 to 3A size was the long way, and I saved the scraps, so I just measured the 10" side. The actual dimension is 9-61/64". (This was with the ruler from a Starrett combination square, which should be reasonably accurate.)