Compact binocular faults

As much as I dearly love my compact binoculars, I know quite well they have faults and shortcomings. All compact binoculars have shortcomings, thanks to their diminutive optical systems. Yes, there is an optical penalty to pay for that small size and weight that makes compact binoculars such a joy to carry.

However, much of this is exaggerated. Are small binoculars as bright as large binoculars? No, not on paper, but for all but the most extreme low light applications, compact binoculars are bright enough. Yet this lack of image brightness in compact binoculars is the shortcoming most likely to be raised by some so-called binocular experts, probably because the math involved is the easiest to explain to the uninformed. Lack of image brightness is only rarely a reason not to buy compact binoculars.

With my compact binoculars, I am more aware of a decrease in resolution (the ability to show two closely spaced objects as separate objects), compared to my larger binoculars. Resolution, after all, is directly related to objective size. However, my compact binoculars offer all the resolution I need, even for detail daytime work such as birdwatching. I have never failed to identify a bird because my compact binoculars lacked resolution. This lack of resolution is something I notice much more for astronomy and that's one big reason why we astronomers go larger on our astronomy binoculars.

Eye fatigue that comes with using compact binoculars is perhaps the most valid criticism of compact binoculars. The pupils of your eyes must be lined up precisely with the small beams of light – exit pupils – leaving the eyepieces of compact binoculars. If your eyes are off even a bit, strain can develop. Over long observing sessions this can take a toll. Experience in handling compact binoculars can help, here, but even for an experienced user of compact binoculars like me, I find mid-sized and full size binoculars a better choice for all day, continuous observing.

Still, I do just fine with compact binoculars for most uses. They’re not quite the optical nightmare some would have you believe anymore than they are the perfect solution for every application as others might claim. Compact binoculars are, however, ALWAYS better than no binocular.