At the risk of revealing my age, I can tell you that there was a time in the
spotting scope world when 60 mm
spotting scopes were standard fare and the big 80 mm and larger spotting scopes had yet to hit the market. Most of us birders did just fine with those smaller spotting scopes, by the way, but once those 80 mm
birding spotting scopes appeared, the rush was on to the larger scopes.
Bigger spotting scopes are still in vogue in the
birdwatching world, but a lot of us who hit the birding trails and carry a spotting scope and
tripod for hours at a time all have gone back to the smaller spotting scopes to save on weight and bulk. It’s a good plan if your jumbo wonder scope seems to be getting heavier with each passing year.
A smaller 60 or 65 mm class of excellent optical quality will truly do just about everything a serious birder will ask and will do it cheaper than the same model in a larger size. My old
Kowa 663 with its excellent 20-60 zoom eyepiece, for instance has never failed me. I still have and use heavier spotting scopes when there is no need to carry them far, but when it comes time to hoof it down the trail, make mine a
small spotting scope, please.