8mm Forum: Film fades even in sealed conditon, how come?

This is topic Film fades even in sealed conditon, how come? in forum 8mm Forum at 8mm Forum.

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Posted by Winbert Hutahaean (Member # 58) on June 03, 2012, 07:49 PM:

Following the discussion in "What Films did you show last night? " thread, I want to ask your opinion how can color film can fade even in sealed packing.

I thought the fading process will take place when the picture cells got hit by sun or light bulb. If in sealed condition which means in total darkness what then trigger the fading process?

Posted by Pasquale DAlessio (Member # 2052) on June 03, 2012, 07:56 PM:

As far as I know films have to "breathe" in order not to turn. That's why some of the plastic film cases have removable tabs to vent the film. I guess it's some type of chemical process that takes place when they are air tight that turns the film. Perhaps some one else in the forum has the technical jargon for it. [Confused]

Posted by Hugh Thompson Scott (Member # 2922) on June 03, 2012, 08:14 PM:

As far as I can gather Winbert,film does need to breathe,and
sealing up film in airtight cans and shrinkwrap, can damage them
especially if they are acetate based,The fading of the colour just means that the dyes used are coming to the end of their life and
I suppose temperature and humidity must have an effect on the
speeding up of this process.It sometimes puzzles me when some
of our members say with understandable dismay that a well loved
film has faded,and when I check my own copy,find it's okay,then
that makes me wonder what conditions are different to mine,
what chemicals have been used to clean/lubricate,what kind
of light has been put through the film and what stock is it
printed on.I can remember when "JAWS" was big back in the
mid 70's,and this was reported in the National press over here
that there were concerns over the saturation of colour,where
the blue sea wasn't as blue and the reds weren't as red,I have
always felt that the powerful lights on 35MM projectors must
have an effect on colour,but the prints don't seem to survive
to inspect after their circuit release.

Posted by Bill Phelps (Member # 1431) on June 03, 2012, 08:30 PM:

About two years ago I bought a sealed copy of Beneath the Planet of the Apes 200' sound/color and it is faded. It was nice to be the first one to screen it though. It still had some color. I thought color fade had more to do with temperature than exposure to light.

Bill [Smile]

Posted by Joe Balitzki (Member # 438) on June 04, 2012, 03:46 AM:

Lets not forget Kodak's disclaimer which was on their packaging because in time all color dyes will fade. They probably could have developed Low Fade print stock earlier. But delaying it allowed them to sell more film. In the meantime, AGFA was ahead of them when it came to dye stability.

Posted by Hugh Thompson Scott (Member # 2922) on June 04, 2012, 10:47 AM:

Hello Bill,yes temperature must have a bearing on film fade,but
the high powered light that is put through film,and the heat
that is hitting the rear of the film plate must be a factor in dye
fade.For instance,in India,where curried food is popular,if it gets
on clothing is very difficult to remove,being a natural dye,The
ladies in India just let the sun bleach out the stain.I know the spectrum of sunlight is different to tungsten,but the fact remains
that a lot of light and heat is focused on a small frame for a short time.Have you noticed on some of your old films,if you
have white film as tails,how the frame from the projector gate
is shown as a dark imprint through the length of film,and thats
only from a 100w QI lamp.

Posted by Osi Osgood (Member # 424) on June 04, 2012, 12:55 PM:

Temperature definitely does have a part in fade ....

I decided upon a little experiment once. I had two somewhat faded copies of "Close Encounters of the Third KInd" (the digest). They still had decent color, but the process was already started.

I took one, placing it in a freezer storage bag with selica gel packets in the bottom of my frost free fridge ....

The other, I tossed in the bin outside! It was the middle of summer mind you, and it was a three week over one hundred degrees period of time.

I went outside to look at the print that was in that big old dumpster, as it was to be dumped by the city the next morning. It has been four days, and that print was absolutely, totally, beet red with no color left at all.

When I finally sold the other print, two years later on ebay, it had not faded further one little bit.

This is why some people are flabberghasted when they swear, (on ebay), when they last played them, (God knows when THAT was), the color was fine, but then they add, "But they were safely tucked away in attic, (gasp) or even worse ...

My metal storage shed in the back of my house!
(double gasp!)

Now, you can't stop fade once it has happened, and sooner or later, those film dyes, on eastman, kodak SP, (Fuji, in some cases) will fade, but you can hold off that process for a very long time and have a fun collection to enjoy for much longer than you might expect.

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