Unbending bent slide film.

[andysig]

I've just got a number of rolls of colour slide film back from the lab. Each film is cut into 5 exposure strips. In each strip which has exposures around #17 displays a fairly severe curve which indicates to me that instead of the films being hung vertically to dry before cutting, they were probably draped over a bar or something similar. Now of course some very scannable shots occupy position #17 and I want to straighten the relevant strips of film out.

The solution I have in mind is to soak them in distilled water at around room temp (20 deg C) and then hang them vertically and weighted. Is this likely to work or can anybody suggest a better solution?

Thanks in advance.

 

[chamon88]

It's a dip'n dunk process ,the film is load on a hanger and go dry to dry from chemistry to the dryer on that
Hanger , with time the curve disappear , if you put it in water you need the stabilizer it's like the photoflo in bw
If not you will have drying mark on your film.

 

[Worker 11811]

What is the radius of the bend? If it's not too severe just hang the film and put a weight on the bottom.

I see this problem in the cinema all the time.
Film is shipped on reels with smaller diameter cores than the platter it will be projected from. Some film comes on reels with 4 in. centers. Other times it comes on 1 in. plastic cores. By the time it reaches the theater, the film has often taken a "set" into the size of the reel it was shipped on. It's especially worse if the film has been stored for a long time.

When you unwind film from its small core and mount it on a platter system with a center diameter of 18 to 24 inches, you can see ripples in the film where it was unbent from the small diameter shipping reel. The ripples will form a visible spoke-like design in the large film roll. "Spokey" film does not play well through the projector, especially projectors with straight gates. (One reason why most projectors made in recent years have curved gates.)

The first few times you play a "spokey" film, it will be jittery in the gate. After it's been on the platter for a while (a few days) it will relax and flatten out. It will eventually run through the projector smoothly.

Bottom line: If the film is not bent around a small diameter, just hang it under tension and straighten it. It will take a while but it should flatten out.
I'd say 1 inch is the smallest diameter I'd try this with.

Also try carefully warming the film to speed the "unsetting" process.

 

[Athiril]

hot water (not boiling, but say tap hot), water quality suitable for rinsing and drying film afterwards, wet film and 2 slides of glass (same cheap photo frame glass), place film between two slides of glass, so that it is sandwiched flat, place the entire thing in the tap hot water for about a minute. Take it out, hang it up to dry.

You can also do a similar thing but dry, have the film in it's plastic sleeve, heat up with a hair dryer on both sides, then press it flat against a cool surface.