Can summer heat damage processed negatives?

Hi all,

 

I store my negatives in plastic boxes, inside print file sleeves with a silica gel pack.

 

I always panic in the summertime with the heat. Will summer heat damage negatives? Is it a slow degradation that's not like ferrotyping?

 

Interested to hear some longtime photographers give anecdotes of their experience storing film through hot summer temperatures (no air conditioning).

 

Chris

Dry heat can damage dyes in color images, but the worst combination is high humidity combined with heat.

 

Be very sure that the sleeves are archival.

Folks stored negatives and slides for a long time before there was home air conditioning and many are still in fine shape. Just pick the coolest dry place - I usually add dark to the list. I have scads of stuff still in good shape from years when my living spaces were not A/C.

Dark is more important than temperature - as I found when I accidentally left a strip of B&W negs on a windowsill.

 

The days of sulphur-polluted air are over in most civilised parts of the world, so it's not quite so important to exclude air from the film these days.

 

Anyway, as long as B&W film is properly fixed and washed it's going to be quite stable against temperature. Not so much against high humidity. - Just buy a decent 'glassine' folder storage system and keep your film in the dark.

Chemists broadly classify chemicals as organic or non-organic. From olden times, organic chemicals were substances that naturally came from plant or animal life. When chemists were able to produce benzene in the laboratory, scientists were astounded. Now the lines between organic and non-organic were becoming blurred. A key attribute of organic mixes is, they exist in very narrow surroundings. Change the pH or the temperature or the chemistry of the surrounds, and this will profoundly change their appearance. The egg is a prime example; heat changes the albumin to a white solid.

 

I tell you this because photo films and papers are comprised of a gelatin binder that locks the image in place. Now traditional black & white images consist of metallic silver imbedded in gelatin. Traditional color images consist of three organic dyes imbedded in gelatin. In both cases the gelatin is fabricated from animal bones and connective tissue.

 

Gelatin is only somewhat unchanging. It is hydroscopic (takes on moisture from the air). When wet or damp, it expands much like a dry sponge. When dry, it shrinks. The chief adversary of gelatin is the "beasties". We are talking molds, mildew, and microbes. They love to dine on gelatin emulsions. As a sidebar, gelation has low solubility, it is transparent, it is flexible, and its structure allows the chemicals of the process to enter, percolate within, and then get flushed out. No suitable substitute. Take heart, egg whites preceded gelatin in emulsion making.

 

As to archival quality black & white, property processed, is likely good for 500 years. Color films and papers, likely less than 100 years.

Say what you will about format, this place is high value, due to some very good contributors.

Thanks.

Say what you will about format, this place is high value, due to some very good contributors....

 

Hmm... thank you...

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