@paulhenry3443 - My experience with birdwatching has taught me that holding 10x binos steady on a windy day can be difficult when looking at birds. I would suggest the 8x. I think 8x42 offer the best in terms of looking for birds. The rule of thumb is to spend as much as you have in your budget. A lot of the more expensive binos help you see in low light (dawn or dusk). One factor is the "eye relief", if your brother wears glasses you will want a longer eye relief so he can use them with his glasses on. Another factor is the "close focus", how close can you get to the object you are look at. A shorter close focus is helpful when looking at butterflies, bees, and invertebrates. I hope this helps.
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