The Binocular Sky


How to Evaluate a Binocular

There are some reasonable-quality inexpensive binoculars available nowadays. There are even more very poor quality inexpensive binoculars available. Here's some hints on telling the difference. These tests are done in daylight., either in the shop or at home if you bought by mail order (you did check the returns policy, didn't you??)

If you are satisfied with the binocular you have evaluated, buy that one, not an untested one in an unopened box!

These next three steps enable you to compare different binoculars:

The next two steps are easier if you can "fool" your vision into thinking the objects in each side of the binocular are different. The easiest way to do this is to use different colour filters on each side, such as cellophane sweet wrappers or the red-blue 3-D spectacles.

Additional tests for Used Binoculars

Acknowledgement: I am indebted to the following members of Stargazers Lounge forums, all of whom have made suggestions for inclusions or improvements to this page: cantab, mdstuart, pete_gamby. (If there's anyone I've missed, I apologise, and please tell me!)