Print viewers
From Photo-3d
Since print images come in a variety of sizes, there are choices. The standard Holmes card is 3 1/2" x 7".
[edit] currently manufactured
Check with the various 3D suppliers, among them are a number of viewers for 3D print pairs. They generally fall into these categories:
- Fold-flat viewers
- Single piece - these are a one-piece plastic handle with two lenses molded into it.
[edit] no longer manufactured, available used
(Thanks to khamilto AT houyhnhnm.prime.com, from which much of this was paraphrased.)
There are relatively common aluminum-hooded viewers available used which were manufactured around the turn of the century. They often have the imprint of one of the big 3: Underwood & Underwood, Keystone, or H C White (which called its scopes Perfecscopes) on the hood or on the underside of the tongue near the handle.
Condition is an important consideration. Is the original felt intact? Details can be significant too: often, the folding handle is unsteady. Certain locking designs in the handle are better, in my opinion. I've seen tigers maple quoted as a premium consideration, but I believe that usually refers to a wooden-hooded model. And still, I think the distinction may be overrated.
Unusual, older models rate higher prices if in good condition. A pedestal model with the Joseph Bates blindstamp could easily be worth $150. But the older models are less generally useful than the later models which have superior optical qualities.
Beware also that some reproductions of the metal-hooded viewers are out there, easily distinguished from the real thing.
These viewers hold a 3½" x 7" card, with two 3" square photos on it.
