Discussion in 'Film and Processing' started by tara_ratliff, Oct 2, 2010.
How long does Kodak Portra 120 print negatives last after development if stored properly?
Tricky question. The latent image starts to degrade moments after it is taken but I have had exposed film in the refrigerator for a few months on a trip that processed well upon my return.
I have heard stories of years of proper storage but for best results the quicker the better.
I believe Tara is asking about the longevity of color negatives, not color film.
OOPS Sorry I was multi tasking... I need to pay more attention. Well if stored properly in acid free holders in a dark place many many years. Keep the dry.
Heck of a week after 7 years at the same job I am now unemployed and I am going to have much more time to pay attention.
Thanks for keeping me straight James.
Larry: sorry to hear that.
Tara: This depends a lot on storage conditions. Kodak Tech Pubs have a lot of material of this type. From the one for Portra (pub # E4040):
"Process film as soon as possible after exposure. Protect negatives from strong light, and store them in a cool, dry place. For long-term storage, keep negatives at a temperature between 2° C (35° F) and 13° C (55° F) and at a relative humidity between 30 and 35 percent."
Also, Tech Pub E-30: <link> has more detailed information.
I recently scanned some negs from the 80s I found in my mother's basement. The storage conditions weren't perfect, but the results were surprisingly good. Hard to tell how good they were compared to if the film had been new, there's been so much development since then and 3200 PPI desktop film scanners didn't exist then, but the color was very good, better skin tones than most digital shooters get now, plenty of grain but 400 film was grainy back then. So there's hope.
There was a time when manufacturers routinely published image permanence data on their products. Henry Wilhelm compiled much of these data in this publication in 1988. Obviously this was long before Portra films were developed, but we can get an estimate from Portra predecessors, namely Vericolor III. The criteria that Wilhelm tracked was the time until a 20% loss in the least stable dye. He rates Vericolor III at 38 to 65 years for a 20% loss in the yellow dye. My best guess is that Portra is in that range.
In 1988 when optical printing was the only game in town, a 20% loss in one of the dyes made it somewhere between difficult and impossible to get a top quality print. In this days where scanning predominates, I've scanned early Kodacolor negatives where over 50% of the yellow dye was gone. It would take Portra something like 100 years or more to fade this much. The resulting image was superior to any optical print that could have been made when the negative was fresh.
Bottom line: store them carefully and the negatives will outlive you.
Tara, My color negs are all over the board. I have many that have faded considerably after about 25 years, and others that have not. They were all pretty well stored for their time, in glassine envelopes, though I don't use them any more. I believe it has a lot to do with the way they were developed. The ones sent to questionable labs didn't fare so well, but ones sent to excellent pro labs seem to last longer. I would say, "don't scrimp on the lab you choose."
For CN films it depends how good or bad the last process bath was done. I am talking about the stabilizer bath containing Formaline to remove not used color couplers and the stuff is killing all organic materials.
When putting the negatives in sleeves according ANSI IT9.16/DIN ISO 10214 , archival, it will be around 25-30 years before starting fade away.
B&W negatives have a longer lifetime.
I have some chromes that are about 35yrs old and they look fine. I have some B/W medium format from my grandparents days and they up to about 100 yrs old and they look good. I used to shoot mostly E-6 and do not have any real old C41 much past maybe 10yrs. . I just keep stuff in shoe boxes in the closet. I live near Monterey and the weather is mostly like a nice spring day. I think Kodak says that E-6 is good for 80yrs but I am not sure about that. I tell folks to shoot a few rolls of B/W of their kids once in a while so they can have negs to save but nobody listens to me. They just shoot the digital and a couple years later the pictures are gone.
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