Scope Eye Relief/Variable Power Question

[Col. Plink]

Hey y'all,
If a scope is listed as variable power (e.g. 3-9x) and a range of eye relief (e.g. 8-13"), does the eye relief DEcrease as the magnification INcreases, or the other way around?
THANKS!

 

[WNTFW]

It seems to me eye relief and exit pupil become less forgiving as magification increases. In other words the range of too close vs too far is less at higher than at a lower magnification.

 

[kis2]

agreed. the lower magnification ranges generally have more eye relief, better resolution, etc...

 

[Col. Plink]

So higher magnification means LESS eye relief (where both are variable)? Thanks!

 

[Col. Plink]

I need to know if the above statement is true. Thanks!

 

[rcmodel]

Yes, it is true.

It all relates to the size of the exit pupal.
(Power/Objective lens size)

A 3-9x40 would have a 13.3mm exit pupal at 3x, and a 4.4mm exit pupal at 9x.

The human eye can use at most, about 7mm, so anything over that is free to move your eye around in and still see through it.

Anything less then 7mm becomes increasingly more critical for the eye to be centered behind the point of light coming through the lens system.

rc

 

[jmr40]

Most of the time, yes. But some scopes have the same eye relief at all powers. The Zeiss Conquest for one.

 

[Uncle Mike]

Most of the time, yes. But some scopes have the same eye relief at all powers. The Zeiss Conquest for one.

Eye relief is the distance from the rear eyepiece lens to the exit pupil or eye point. It is the distance the observer must position his or her eye behind the eyepiece in order to see an unvignetted image. The longer the focal length of the eyepiece, the greater the eye relief.

The 'exit pupil' decreases as the magnification 'increases', and the 'exit pupil' increases with a decrease in magnification.

Eye relief changes on most hunting rifle scopes. Most scopes are variable magnification, and eye relief depends on magnification. When the scope is adjusted for higher magnification, the eye relief will decrease; when it is adjusted for lower magnification, the eye relief increases.

 

[jmr40]

Uncle Mike, I'm not sure if you quoted me to disagree with me or agree with me. With most scopes you are correct.

I like Leupold at least partly because of the generous eye relief they offer. For example mine have 4.7" of eye relief at the lowest setting. 3.7" at the highest setting. That is a full inch more than most of the competition.

But the eye relief does not change as the power is increased on all scopes. My Zeiss Conquest remains a constant 4" at all power settings.