Cutting down 8x10 film
I often see boxes of 8 by 10 film which if I quartered would be so much cheaper then pre-cut 4x5. I'm talking about transparency and color film here so do you think my lab would take home cut sheets? I know that the notch coating designates type of film, when a sheet gets processed is this code read by a machine (in that instance 8X10 cut down obviously wouldn't work).
I don't know of a film developing system that reads notch codes. Thats usually for the person loading/unloading film holders, so they can determine which emulsion is loaded(or otherwise). Dip n' dunk systems are pretty brainless, the more elaborate machines have little "flags" that push a small switch telling the machine to develop that rack a certain way(normal, pull -1/3, +1, etc..). Some machines can be controlled down to 1/10 stop in terms of push/pull processing! However, color film is a SET process, with little that can be done in a lab situation outside of push/pull development to control contrast. Most slide films don't exhibit a color shift(at least a visibly noticeable one) up to a full stop PUSH. PULL processing, however, is a completely different story. Since color film's "normal" is a certain duration, each of the layers in the film need to be developed FULLY. The outer emulsion(s) get more development than the ones beneath it when PULL processing, generally exhibiting a color crossover, or lack of saturation of a certain color.
I remember reading the brochure from a long-gone lab that used to serve pro's here in LA. They advertised up to a 10CC color correction in their E-6 line, IDK exactly HOW they'd do that, but I guess it was a marketable service that some people used enough to put bold font at the bottom of the price list. It was nice to see 8x10 E-6 processing for $4.50/sheet too . 8x10 chrome dupes were $18 IIRC. My how the times have changed...
back on topic . If you're wanting to cut down 8x10 film to 4x5, it can be done. I haven't personally done it, although I've cut film down AFTER processing to a 4x10 ratio . Of course, when the negative/chome has been developed, its easier to see what you're doing in the room light!
The best way, IMO to do this would be to get a guillotine cutter, or a rotatrim, one with a large enough flat surface to make some "stop marks" to zero out the edge of the film against for your long and short dimensions. If I was you, I'd wear some of those cotton or nitrile gloves, just so you don't put your "mark" on the film itself.
I do this with Lith fim and a box of 25 8x10 old tech pan that came my way for the very right price of $5. It is a pain in the ass.
4x5 film is not exactly 4x5. My blade cutter tends to want to make the film 'walk' while I lower the blade, so exact, non perfect cuts happen.
Dust is a major bitch to control.
I clip one corner, rather than notch it.
my real name, imagine that.