Preservation of Photographic Materials

Thanks to some help from the federation, I was able to attend a workshop on how to take care of photographs to preserve them for posterity. It was given at a research center here in New Orleans, with experts from Washington, D.C. and Atlanta, Georgia.

One thing we can all do that will help the most in preserving our photos, is keep them in a place that is not too hot or too damp. For instance, Andrew said that you are not comfortable in the hot attic or the damp basement. Neither are your photos. A good rule of thumb is: keep your photos where you are comfortable -- they will be comfortable there also. Even though you cannot sustain the ideal temperature and relative humidity, anything you do to keep them down will help preserve the photos that much longer. The ideal relative humidity is from 30-40% Damage is greatly increased above 70% relative humidity. High humidity does more damage than high temperature. For instance, 90 F and 10% RH is slightly better than 70 F and 50% RH. Dropping the temperature 10 F will double the preservation time of your photos.

If anyone out there does their own developing and printing, do NOT use the RC paper. It is not stable. After even three years you will see fading and deterioration. Get photo paper that is made with fiber. I have found it necessary to go to Ilford, an English paper. Kodak does not put out much fiber paper any more.

A no-no is putting photos in those so-called "magnetic" photo albums. There is nothing magnetic about them. The paper is lined with rubber cement, and the adhesive will mark the photos in just a few years, staining them badly. Nor can you pick them up and move them later on, as they claim. After a not-too-long a time, they will be permanently fastened to the page. There are many safe ways to keep your photos. Some are more expensive than others. You can purchase acid-free photo album pages and fasten the photos down with those old-fashioned corners that you could buy years ago, but now you can even buy acid-free corners. If you use those corners, Andrew said not to make the photo tight in the corners. Give the photo just a little play, so that when the paper swells and shrinks, the photo won't bend and crack. There are Mylar page protectors to fit over the photos, just like you do with page protectors for paper. But some of those page protectors are not of archival quality. Mylar is. Do not buy PVC plastics. Either uncoated polyester (Mylar is the brand name), polypropylene or polyethylene are okay to use. I have some called "Print File Archival Preservers", and while some that claim archival quality really aren't, this one says "NO PVC", which means it is okay. You can get pages with pockets of different sizes to hold your photos. Some have three-hole pages, and others have four-hole pages. Albums to hold either one are available.

We were given catalogs that are very good, with many choices, and not requiring a huge order. If you are interested, the address is: University Products, Inc./ 517 Main Street, P.O. Box 101/ Holyoke, MA 01041-0101. For customer service and questions: 1-800-628-1912.

Most of us do not have really old pictures and negatives, i.e.: 19th century. The following dates for types of prints:
Albumen prints (egg white)  1855-1885
Daguerreotype (positive) 1839-1860
Ambrotype (glass) 1851-1870
Tintype  1856-1880

As for negatives, cellulose nitrate was used from 1889-1950s, and then, because it is so flammable, Kodak developed cellulose acetate from the 1920s to the present. It was called "safety film" because it was safer to use. The cellulose nitrate caught fire easily, especially in movie projectors, so when home movies became possible, Kodak didn't want to be responsible for house fires, and developed the "safety film". The cellulose nitrate was easy and inexpensive to make, plus it was strong and durable. The cellulose acetate is expensive to make, is weak, and unstable. But the cellulose nitrate is not only highly flammable, but hard to put out if on fire, as it feeds on itself, producing its own oxygen as it burns.

Speaking of home movies, one thing that is NOT recommended is having the 8mm film transferred to Video tape. The Video tape is very, very unstable. Also, the machinery for viewing it will be obsolete before long. It would be easier to get your 8mm projector repaired and coaxed into running than to be able to view your Video tape after just a few years.

There isn't anything you can do about faded color pictures, but the reason the colors change is as follows: the chromogenic dye is in three layers, and the magenta dye fades first when exposed to light, leaving a bluish image, while the cyan dye fades first when the temperature and humidity are high, leaving a reddish image. About all you can do is not hang colored photos on the wall, and try to keep them in a place with moderate temperature and humidity. As for colored slides, Kodachrome has excellent dark stability, that is, it is not affected as easily by high temperature and humidity, but has poor light stability. On the other hand, Echtachrome, before 1988, has poor stability all the way around. Since 1988, it is comparable to Kodachrome.

To preserve your negatives, the only way to keep them for a long time is to keep them in "cold storage". That means in a refrigerator or a freezer. Both cellulose nitrate and cellulose acetate are unstable. I don't intend freezing ours, but if you do, be sure to put them in a zip-lock bag first, and when taking them out, leave them in the zip-lock bag until fully thawed out and room temperature. When thawing, the outside of the bag will sweat, not the inside. Also, the bag will protect the negatives from any accidental spills in the freezer.

If you have shelves that you intend keeping your pictures and negatives on, wooden shelves are the worst. Avoid wooden furniture. Sprayed coated metal is best.

If you have the misfortune of getting your photos wet, such as a flood, which happened just outside of New Orleans to the O. Carms last year, your best bet is to freeze the photos immediately, and then as you have the time to handle them, thaw them out and air dry them. Remember, the coating on the paper is gelatine. If you just happen to get a photo wet, don't panic. Just immerse it in water so it gets wet all over, and then air dry it. This wasn't in the workshop, but I know from darkroom work that it's okay. After all, when you expose the photo paper in the enlarger, you then submerge it in developer, then a stop bath, then into hypo for five minutes, and then wash it for as much as an hour in running water, so water isn't going to hurt it. But if you spill coffee on it, especially on a black & white photo, it will tone it brown -- been there, done that, but on purpose.

Having worked in archives, and taken a course in it once, I take it for granted that everyone knows that the acid in paper turns it yellow, brittle, and then crumbly. If you are not familiar with this fact, let me remind you that nothing is more painful, a little cut that is, than a paper cut. That's because the paper has acid in it. The paper used for newspapers is made of wood pulp, and has the most acid, which is why it turns yellow so quickly, and turns brittle. Today some regular papers are actually acid-free. Companies that sell material for archivists have special acid-free paper, plus some papers and boxes with a buffer to keep the material even longer. In some rare cases the buffer can do damage, but I think that is only in the albumen prints, which few, if any of us, have.

Some recommend wearing cotton gloves when handling photos, but Andrew is ambivalent about gloves. He said that it can defeat its purpose if you touch your face and arms with the gloves, because then you have the oil from your skin on the gloves, the very thing you were trying to avoid. When handling photos, try to keep your fingers from the front gelatine surface, holding them by the edges or touching only the backs. Even if your hands do not seem to be oily, they are.

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