I am not certain that I have this question in the correct area here. I have a copy of this in B&W: film, paper, chemistry. I was given some Dupont, Graphic Arts Film with no data sheets for it. I says 738 Cronar, CCS-7, Commercial S Film, either .003 or .007 Thickness and it is 24" x 32" in size (that is correct; Inches). I can do all kinds of things with it from cutting it down and using it in pinhole cameras, to making 4X5" sheet film out of it to enlarging negatives onto it and then developing the resulting "positive" that is on the film and then projecting that onto paper to make a 'negative' print. However, having no data sheets, I have no idea what the ISO/sensitivity is or how to use it in terms of exposure times for any purpose. I do plan to take an 'alternative processes' class at some point but would like to get at least a feel for working with this film first. I have searched the internet for this film type and found Cronar but nothing else and what I can find about it so far is zero, nada, zilch. Now, I know some of you might want me to send it to you, but my mama didn't raise no fools, and my grandma, she raised me.... Any help is much appreciated.