We preserve old photos by placing them in mylar sleeves we get from Light
Impressions in Rochester. The sleeves are then put into acid-free paper
envelopes, and identifying information is written in pencil on the envelopes.
If someone wants to use one of these old photos in a scholarly publication, I
take them home and make copy negatives and prints. (It is not cost-effective
for the society to have its own lab.) Often I can improve the contrast of the
copy print so it will look better when printed with a coarse screen.
The portrait that is sharp in the center but not the edges was made with a
soft-focus lens. This has been a popular portrait technique almost since the
beginning of photography in 1839. "Pinkham and Smith" were one of the better
manufacturers of soft focus lenses early in the 1900's (I almost said this
century!) and some are still being used on 5x7 and 8x10 portrait cameras with a
Packard shutter. Some of the modern soft focus lenses available from Mamiya
and other manufacturers were designed by analyzing the Pinkham and Smith
formula.
Sometimes, old photos in good condition sell well in flea markets and antique
stores, but they do not command high prices unless of some well-known person,
place or event.
Email me at dave...@aol.com if you need more information.