I’ve used a variety of inferior binoculars over the years, always letting them gather dust because they disappointed in various ways, mainly optically. They were not a pleasure to use, and/or caused eyestrain*.
Now I’m testing a pair of the green Zeiss 8X32 Victory T* FL binoculars. I chose that model for top optical quality, and an ideal compromise between brightness, size and weight. The view through them is gorgeous: very bright, crisp and clear, and totally devoid of any color fringing or artifacts even in adverse viewing conditions, such as dark branches against a bright sky. They also peer into murky areas otherwise un-seeable. I haven’t quite figured out if I want to deal with larger and heavier 42mm objectives, or 7X, 8X or 10X magnification— I’m still researching things. The 7X are appealing for a wide-field view, but 10X is appealing for the mountains across longer distance. But as it stands, I’ve never used a better binocular than the 8X32 Victory T* FL.
I’m very impressed with the Victory 8X32’s, and I enjoyed watching the crows and other birds on my bounteous persimmon tree peck away at the fruit; they always fly off when I approach. The clarity is startling, and now I see how birders enjoy sighting new species. It’s also rather interesting to examine things at relatively close range: plants, small animals, etc, and I found that doing so gave me some photographic ideas.
Update Dec 9: several readers have written to express strongly that in their experience eye relief is a critical factor, at least for eyeglass wearers. To explore this issue, I have some binoculars with 19mm and 20mm eye relief; the Zeiss Victory line tops out at 16mm, as does most of the Leica line.
The Zeiss 8X32 Victory FL binoculars are not inexpensive, but the good news is that there is a $250 rebate through the end of the year on many of the Victory line binoculars, and certain other models. See my list of appealing binoculars at B&H Photo .
The Victory lines comes in green and black; I slightly prefer green. The “FL” designation means fluorite, for ultra-clean imaging free of color aberrations.
Eye relief — the Victory line has eyecups that extend or retract, to accommodate use with or without eyeglasses or sunglasses. They also have diopter correction. Some models have up to 16mm of eye relief.
At least one reader states that he wouldn’t touch binoculars with less than 18mm of eye relief, which seems to rule out the entire Zeiss Victory line, and most of the Leica offerings as well, with this notable exception. I hope to see for myself by trying some brand with 18mm or 20mm or eye relief.
Magnification — I find that 8X magnification is about all I can hold steady. Moving to 10X things start to get a bit shaky for me, though I have yet to test that theory with a Zeiss offering. Mountain users might prefer 10X for longer distances.
Exit pupil — Binocular exit pupil size is really an issue for dim light. With really bright conditions, 42mm or 56mm binoculars might be too bright for comfort. A large exit pupil size is a moot point in bright light: the pupils in your eyes will be contracted to a small size.
if you’re older (40's on up), the pupils in your eyes can no longer dilate as they could in youth. The exit pupil size of a binocular is essentially the circle of light it projects, so if your pupils can only dilate to 4.5mm, a larger exit pupil is of no benefit. For someone in the late 40’s or older, a binocular exit pupil larger than 4.5mm or so is unlikely to be of much value. And the larger the exit pupil, the larger and heavier the binocular. This varies by individual physiology, so there is no fixed value, the very picky user will need to try several models.
In short, your eyes can’t make use of a large objective diameter (42mm, 56mm, etc), which is why I chose the 8X32mm models, which are still very bright, yet with relatively compact size and weight (20 oz/560g), so I will actually take them with me! As a practical matter an exit pupil in the 3-4.5mm range is a great choice; the Zeiss 8X32 Victory model has a 4.0mm exit pupil.