Thread: Midget binos

Divide objective size by magnification, so for 7x35 then 35/7=5mm exit pupil. 8x40s and 6x30 and 10x50 binos each have 5mm exit pupil, so similar light gathering power. Note though that the lower magnifications "win" in the light-gathering department as they have less thick glass letting more light through (and weighing correspondingly less).

The grunty military 7x50s will have a much bigger exit pupil (50/7=7.14mm exit pupil) but the older we get the less likely we are to have pupils that can dilate to 7mm and utilize the extra light available! Dead weight unless you are a 21 yr old soldier.

If you want something you don't tire from, go for lower magnification like 7x35 or 6x30. Minimal shake, maximum light gathering, light weight, wide viewing angle. For an occasional closer view you have your rifle scope.

Individually adjustable tubes for better waterproofing, e.g. WW2 Leitz style field glasses. 6x or 7x have such a deep focal plane you hardly need to adjust them anyway.

Like these - diminutive girl with scoped mosin for scale: