Next, face well-lit wall and hold the binoculars nearly at arm's length, with the eyepieces pointed at you. You'll see the exit pupils (disks of light) floating just behind the eyepieces, as was illustrated above. You might think that exit pupils would always be perfectly round, but this isn't so. The ones on cheaper binoculars often have a slightly "squared off" look, as if someone shaved off, or dimmed, two or four edges. This is a sign of manufacturer's corner-cutting that will slightly dim all the images you see.
If you've looked through a hand-held high-magnification astronomy binocular (let's say 12X or above) and tried to read a sign on which the writing appears small in the distance, you'll know how difficult it is to hold the binocular steady. Even when you've braced your arms on a flat surface or against a tree, the simple act of breathing can make the image move enough to keep a person from reading easily!
There are two separate categories that your binocular use can fall into. The first is bird watching and hunting. These activities generally require higher quality binoculars. Recommendations from the Audobon Birding Society call for binoculars that have a magnification of around 6 to 8 times for optimal bird viewing. Any higher, and you will likely have trouble locating animals in the scope, as you’ll lose points of reference when putting the binoculars up to your eyes. The same should be taken into account for hunting – where getting an animal in your binoculars’ viewing range quickly is paramount.

Depending on the pair you pick, you could see 25 or even 50 times more stars with binoculars than with your unaided eyes. This is not due to the magnification alone, but to the phenomenon of perceptive narrowing driving a flow state. Some people use the term focus, or clarity, to describe the feeling. But it's not an illusion; it's a measurable effect.
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