Brightness/clarity test for scopes?

[Ray B]

I'm wondering if there is a method of testing various scopesights for brightness and clarity- such as affixing a light meter to the ocular end so that it measured the amount of light making it through the scope, and having the amount of light going into the scope at a constant amount so that one scope performance could be measured against another? anyone know of this sort of testing/articles?

 

[375 Ruger Fan]

The 1951 US Air Force resolution test.
https://en.wikipedia.org/wiki/1951_USAF_resolution_test_chart

 

[JGRaider]

John Barsness has a monthly "newsletter" called Rifles and Recipes. There are many, many scope tests done in those over the years. His latest book on optics also has a pretty good run down on what he tested, how he tested, and the results. They will surprise you though, guaranteed.

 

[CAustin]

Ray that's getting into some real science. I'm sure there has to be ways because the makers are always advertising about just those points.

 

[PHOENIX PHIL]

I'm wondering if there is a method of testing various scopesights for brightness and clarity- such as affixing a light meter to the ocular end so that it measured the amount of light making it through the scope, and having the amount of light going into the scope at a constant amount so that one scope performance could be measured against another? anyone know of this sort of testing/articles?

If you can find one of the old light meters photographers used to use WAYYY back when, this will work. I had a guy at gun shop do just that. He held two scopes, one at a time of course, with incoming end against a light bulb or very close to it. And at the ocular end he held up just this type of meter that showed how bright it was. You could clear see a difference on the meter between the two scopes.

But that only covers brightness. Clarity I would think is much more difficult to measure, that's a more subjective parameter.

 

[Buckdog]

all the major scope makers tout claims of light transmission percentage on their web sites. BUT I will make it easy for you if you want the best clarity and brightness get a European scope I would rank them as follows 1. schmidt & Bender 2. Swarovski 3. leica and Zeiss. Buy one of these and you wont worry about brightness and clarity. american buy a leupold but it isnt even close to the others and yes I own all so have looked thru all many times. my 2 cents.

 

[Scott Slough]

In simple terms ... they have instruments that measures luminance (brightness is a perception of luminance) and clarity.

https://en.wikipedia.org/wiki/Luminance_meter and (https://en.wikipedia.org/wiki/Luminance for an explanation of why it isn't brightness!)
https://en.wikipedia.org/wiki/Clarity_meter

 

[Ray B]

Buckdog- Actually I do have access to scopes of S&B, German Zeiss and various grades of Leupold, also some older US brands. I'll borrow some of them and try the light meter test as described by Phoenix Phil for how light makes it's way through the scope and if I can get one of those USAF charts printed fine enough, I'll try a clarity test although the test would be subject to the focus of the scope relative to my eyes- which may differ from the owners.