Some collectors have cabinets that are full of a type of binocular called field glasses. Field glasses are plain binoculars that were generally used for outdoor purposes. The term field glass fell out of fashion in the middle of the nineteenth century when the word binocular became popular.

The second type of binoculars that fill up binocular collector's display cabinets are opera glasses. Opera glasses are small, well suited for indoor events like the theater and concerts. They were often used as a way to display wealth. The upper class had opera glasses that were constructed out of gold and silver, lots of time they were encrusted with jewels.

When you are considering purchasing a pair of pair take your time and really examine the lenses. Make sure that they are clear, without any trace of cloudiness. It is very difficult and usually very expensive to replace cloudy, chipped, or cracked binocular lenses. The same goes for a pair of prismatic binoculars, make sure the Bakerlite eyepiece isn't chipped.

Antique binoculars are often covered with leather. Make sure that the leather looks like it is in good condition. Bypass binoculars that have a leather casing that is cracked, torn, or full of dry rot. Like the lenses, the leather covering is very difficult and expensive to replace. Talk to a local saddlery about cleaning the leather covering.

Study any bumps and dings and dents that the pair of antique binoculars might have sustained during the coarse of its life. Decide if they are significant enough to lower the price of the binoculars.

Make sure all the pieces and parts are still attached to the antique binoculars. If possible, try to determine if all the parts are original. Determine whether the binoculars are still working.

Look for official markings on the binoculars. Any marks that have been printed on the the binoculars will make identifying the antique binoculars significantly easier.

There are several wonderful books available for anyone interested in collecting and identifying antique binoculars. The Antique Telescope Society has a membership of over two hundred collectors and is an invaluable resource for anyone interested in antique binoculars.