A big thanks for everyone giving me some input :clap: When I by a pair of binocs, I am going to get a pair of astronomical binocs in to 25x +/- range. If they are unsuitable for rocketry, then I will use them exclusively for star gazing & tracking the ISS.
The best thing I learned from this thread, is the Zero Gravity Chairs
one is in my immediate future!
Thanks everyone!
I don't want to dissuade you from your choice, but if you can, I'd suggest buying from a place where you can get a money-back return if it turns out not to be what you want. Optics are one of those things where being able to try before you buy is crucial, but unfortunately the best selection and prices are on line. So a good return policy is extremely important.
My opinion is that any astronomy binoculars in a 25x power are going to be extremely hard to use. The weight is going to be very hard to hold steady, and the high-power is going to magnify any microscopic wiggle to the point that the image is going to jump around so much you can't see it. For tracking ISS, scanning star fields, and looking at star formations, high magnification is not important, and past about 10x, it really starts to work against you. Magnification is for telescopes, not astronomy binoculars. Get something with good light gathering ability, and good multi-coated optics that let through a lot of light. In other words, the second number is more important than the first --- big objective lens number, low magnification number. If you divide the second number by the first, it should be around 7, not much less than 6. So 7x50 is good, 7x42 is ok, 7x35, not so great. 8x56, good. 9x63, good. 10x70, good. 25x70, not good, not bright, too much wiggle.
And being able to hold the binos steady with minimum wiggles and minimum fatigue is important too. For example, a 15x100 might have a good ratio for light gathering, but how are you going to hold that weight steady for tracking? 20x100 is even harder to use due to magnified wiggles. 25x100 is harder still.
My strong recommendation for Astro would be 7x50, 8x56, 9x63, fully multi-coated optics, and a good return policy. And any of those should work great for rocket tracking too, just maybe a bit heavier than ideal. Combine that with a zero gravity chair and you are golden!
Good luck with whatever you choose!