double-coated film

[gbogatko]

I quote from "Pictorial Landscape Photography" (The Photo Pictorialists of Buffalo, 1921)

"Our own preference is for Orthonon plates [...]. There are now several other brands of the same type of plate -- orthochromatic and double coated, the emulsion being very considerably faster on the surface than in the lower layer."

I know Forte made a double-coated film (think ASA 100) claiming the same characteristics (a slow and fast coating), but alas, Forte is dead, and I don't have much left.

Are there any other sheet films made out there that are 'double-coated' in this manner?

George

[BetterSense]

Xray film is double-coated.It works fine; I keep track of which side was toward the lens and basically ignore the other side.

[Mark Woods]

Double, and even triple layers, of a given emulsion is common in color film. There is a Red, a Green, and Blue layer, and with higher speed films multiple layers are used. In B&W, I don't know.

[Drew Wiley]

I wasn't impressed with that Forte film at all. Got a much longer scale and far better
acutance with things like Efke 25, Bergger 200, and Fomapan (Arista)200.

[Robert Hughes]

Xray film is double-coated.It works fine; I keep track of which side was toward the lens and basically ignore the other side.

"Double Coated" - does that mean two different emulsions on the same side of the base, or the same emulsion on both sides of the base? Color film is similar to the former: X-ray film is the latter.

[Dan Fromm]

Xray film is double-coated.It works fine; I keep track of which side was toward the lens and basically ignore the other side.

High speed X-ray film yes, and it has low resolution. I have some fish radiographs made with the stuff and they're not as easy to read as they should be. Small fish, though, and very fine details. There are single-coated X-ray films with higher resolution.

[gbogatko]

"Double Coated" - does that mean two different emulsions on the same side of the base?

I believe that's what they are referring to -- one fast and one slow. Fast gets the shadows, slow constrains the highs, all this with red insensitivity, being ortho film.

George

[gbogatko]

Xray film is double-coated.It works fine; I keep track of which side was toward the lens and basically ignore the other side.

Ah. Where does one get Xray film. I assume one must cut it down to 8x10 or 4x5 size?

George

[Robert Hughes]

Ah. Where does one get Xray film. I assume one must cut it down to 8x10 or 4x5 size?

George

You could try CXS Online - I bought some a box of 100, 8x10 sheets for use at about 25 cents a sheet. The emulsion is very fragile, you have to be careful not to scratch it. Search through the threads here; there was a lot of discussion last fall about this film.

[BetterSense]

I don't think xray films have the characteristic you are looking for. They have the same emulsion on both sides of the film.