Scan, or have them scanned, into a computer file. Then enhance the pictures
with Photoshop, or any other photo program (PhotoFinish is much less
expensive and just as good for this purpose), to provide a .bmp, .gif, or
.jpg file. These can be printed by present day photographic printers to
make prints that look like the originals.
If they have lasted for over 45 yrs, I doubt the "proof" prints were on POP
paper unfixed, as they would be long gone by now. You can test a small
portion of a print by putting a black sheet of paper or plastic over it,
with a small hole in the covering over an inconspicuous place on the print
and placing it in bright light. If the spot turns dark, then it's probably
POP paper. (45 yrs ago was 1952, and at that late stage not many studios
were still using POP!) In any case, dunking any old print in hypo can be
disastrous. Again, If you want to try this, put a spot of fixing bath on a
small area of a print and see what happens - it could all bleach out.
Frankly, with the advantages of computer imaging at the present time, that
is the best way to save them. I have been doing this for genealogy groups
(and lecturing on it) for several years. The results are nothing short of
fabulous, with even hard-to-see tintypes, etc., being made into very usable
prints. That is the best way to protect those old images. The only other
way is to rephotograph them, and that's a whole 'nother story! Done that,
and the computer is better.
Sil Horwitz, FPSA
Technical Editor, PSA Journal
silh@iag.net