Warped 8mm film - what can you do?

[Philip Hamilton]

I recently purchased a standard 8mm film on a 50' reel - it has very good contrast and sharpness but the film has some warping causing it to go IN and OUT of focus. It doesn't want to lay flat...

Is there anything that can be done to relax the film ? Wind it tight? Bake it in an oven?

I've been looking for this title and it's fine - except for that...

Ideas suggestions comments???

[Ed Gordon]

Organic film base often shrinks with age and deterioration. It is not always easy to tell by looking at it whether or not it is shrunken (although severely warped and curled film is a tip-off). One indicator of shrinkage is that the perforations will not match properly with the registration pins of a splicer. To get a more accurate measurement of a film’s shrinkage, compare some new leader in the gauge of your film with the original film. If the holes do not line up perfectly, your film is shrunken. For 8mm film it is easy to use a strip of 100 frames--if the original film is short by one entire frame, the film is shrunken by 1%. Film shrunken by more than 1% should not be projected, as the projector’s sprockets or claw will damage it. Shrinkage gauges are available, but they are expensive.

Source: https://www.filmforever.org/

There are methods that some people have tried and recommend to others, but everything I have read indicate that any "fix" will be very temporary. If you get it straightened out, the next step is to copy the film before it shrinks again. Cold storage is recommended to slow further damage.

De-shrinking

If shrunken film is placed in an enclosed atmosphere of acetone, glycerol and water vapour for several days or weeks both nitrate and acetate slowly expand to approach their original dimensions. The effect is not permanent and the film shrinks back, sometimes quite quickly. The process can be speeded up at increased temperatures up to about 30C or at reduced pressures [when the solvents are a larger proportion of the atmosphere]

Several commercial systems have been marketed to "deshrink" film base.

An effective system is Redimension from Restoration House Inc. in Canada. This involves placing the roll of film over an open tray of solvents and plasticisers [such as camphor and dimethyl phthalate] in a closed metal container or in a reduced pressure container in a warm place [about 30C] . Over a period of days or weeks [depending on temperature primarily] the film re-extends and shrinkage of up to 2.0% can be fully corrected for both acetate and nitrate film. The process can be accelerated by using a reduced pressure chamber to increase the vapour concentration in the surrounding atmosphere.
Deshrinking is sufficient to enable seriously shrunken film to be printed on an unmodified printer. The effect is not never permanent and shrinkage restarts after a few weeks but tests done in Canada showed that Redimensioned film did not return to the serious level of shrinkage it started from within a measurable time. Soho Images in London was the only European laboratory licensed to use the process, and now use a similar technique, but it is also used by the Swedish Film
Archive[1996].

It is not known what the long term effects of using Redimension [or any deshrinking process] are but some Redimensioned film is now over 20 years since it was treated and still seems to be in good condition. Some archives are understandably wary of using any deshrinking processes, like Redimension, licensed to users without publishing the formulations of the chemistry involved. For this reason a number of laboratories have devised their own formulations which are published and thus more acceptable to archives.

Today these processes are not much used as a routine for shrunken film as it takes far too long and takes up a lot of valuable space. Also variable pitch pull-down optical printers like the Debrie TAI and capstan drive rotary printers like the BHP Modular can handle severely shrunken film as a routine.

A number of commercial archive film specialist laboratories still use a similar but more time consuming process of leaving film for some weeks in a high humidity. It seems that the film base takes up some water and extends. The process is used to even out irregular shrinkage rather than extend shrunk film fully. The prime value of Redimension [and its related cousins including Rehumid] is that it can produce a printable piece of film from the most extreme material. Crisp and crunchy, shrivelled film that shatters and simply can't be unwound can be treated in the roll until it can be unwound. Most film handled by Redimension or itís related processes today cannot be safely handled any other way and would have been destroyed as unprintable.

Source:http://www.brianpritchard.com/FAOL/c...hrinkidx6.html

I have heard that Camphor can be used to "unshrink" film. There is a Facebook page devoted to this: https://www.facebook.com/people/camp...0067216582855/

I have also heard that ironing the film with a medium heat works. If you search the old 8mm forum you will find a short post on this method.

I would invest in A-D strips to test for Vinegar Syndrome. Even if you can't smell it (yet), it may still be there. See: https://www.filmpreservation.org/pre...negar-syndrome

[Philip Hamilton]

ED - Thanks! Yeah ironing might flatten it out. I don’t think it is shrunken length wise. I will do some measuring with some white film leader to verify. It has no smell but I understand that isn’t always the tell-tale.

[Philip Hamilton]

I lined up the film to some white leader and about two feet out there was a slight shrinkage that I can see in length. So I got a refund…. claiming warpage and shrinkage. It’s a shame because the box was nice and the picture sharp with good contrast - when in focus…..

[Douglas Meltzer]

Philip,

That's so painful, to find the title you've been looking for only to find something wrong with the print. Soaking the film and doing a very tight reverse wind might have worked temporarily, but it would go bad again pretty quickly. Sorry!