Here’s a question for you scope experts.  Is there an easy way to determine the magnification of a scope that’s not marked?  In this case I’m referring to one of the classic ¾” long tube scopes such as the Unertl, Fecker, etc.  Many of these, especially the earlier models, are not marked with the magnification.  A portion of my formal school training was in optics and the answer is not obvious to me.

The only method I know of is to look at a small far away object with one unobstructed eye while looking at the same object through the scope with the other eye.  Then, while superimposing both images over each other, estimate how many times the image seen by the “naked” eye will fit into the larger image see through the scope.  It’s a little tricky and you must have the ability to concentrate on both images at the same time, which some find it hard or impossible to do.

So, is there another easier method?

Wayne

There is actually a pretty acurate/easy way to do this and it is one of the ways the refs check scope power at score matches to make sure guys do not cheat with boosted scopes. They do it with a little diagram that shows the exit pupil size that shows in the eyepiece of certain power scopes if you stand behind it and look at the little image in the eyepiece. What I never knew until I saw the little template with the circles is that they all differ by power and it's pretty easy to tell, just hold up a template and size up the exit pupil .