I was talking about regular use of a 10x (standing, like during a walk, the same way you use a 8x), many people use 10x42 like this, without the need of any support. In fact, some people prefer 10x as a main binocular and find it is perfectly usable as an everyday binocular. There are several threads in the forum about this. Once I opened once regarding this very question, you can read interesting opinions:
I've seen this topic coming up regularly, mostly from beginners hesitating which magnification to choose for their first pair of binoculars, but I’ve searched the forum and have not seen a direct thread on this. Some background: I’ve always used x8. I think years ago someone knowledgeable told...
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Other interesting threads:
I was recently comparing 10x30 bins and 8x32 bins by mounting them on a tripod and viewing UPC labels and small text on various food containers from a distance of about 30 ft, going back and forth several times. In all cases the 10x binos were able to read finer text and separate more closely...
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I bought a Vanguard 8x32 ED. I was happy with them but wanted a 10x so I invested in a Bushnell Legend L 10x42. Wanted a bit bigger for hawk watching and the shorebirds. I really wanted the Zeiss terra ed 10x42 but didn't want to spend the money. I got the other two at good deals...
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In my case I find 8x way more comfortable as an all-rounder (7x even more so, but good 7x are becoming rare; I've been on an endless quest looking for "the 7x", and having tried some of the very best, I have not found it yet).
When I know I'm not going to be doing a lot of forest/bushes, then I take the 10x42. The Nikon SE 10x42 offers me a really steady view (many people find porros easier to hold because they're wider). I've even used several 12x binoculars and for the same use they were reasonable good (the Monarch 5 12x42 was quite nice handling-wise), but mostly I don't find a great advantage of 12x above 10x. What I find worth noticing is that 10x is very personal... even changes with days. Some days I take my 10x42 SE and I'm amazed of how still I can hold them, basically like a 8x (and I'm not talking about wind or lack thereof), I get a clear an steady image, full of contrast and details, but some other days, I find 10x too nervous (maybe too much coffee?). I don't know why, but some days 10x simply don't work for me.
As for the 10x50 Viper, I've found the ergos quite nice, very different to the SE. I like the fact that the barrels are wide at the end, so you can grab them from there and get a very stable view (this is a classic holding technique to get a quieter view, holding the binoculars by the further bit, by the objectives, not by the nearest-eyecups, like on smaller binos).
I agree with you, if I was going to sit or use something as a stand, I'd use 15x, etc.