Conclusions so far
Not that it's a huge sample, but the results are about what I figured:
Most people use a spotter to see bullet holes (or otherwise spot their shots) and/or to dope the wind while shooting, or while in close proximity to the shooter.
A few people use a spotter to locate game, so I'll define that as a secondary application, which could probably be satisfied with some 10 x 50 binocs. With much greater magnification than that, you'll need a stand for the optic. Otherwise the jiggle from touching the optic will tend to erase any additional resolution.
That's why I can't figure out why some "spotting scopes" are made at all. To my thinking, there are some of what we in the design business call "constraints" that aren’t being met. If you're building automobiles for instance, one definite constraint would be that the car must have enough room for a driver. Another constraint would be that the car must get you (and some minimal amount of your stuff) from point A to point B faster and/or easier than walking, etc.. You get the point.
There is another class of requirements that I'll call "design goals". For a car, one design goal might be that the car must be visually attractive. Another would be that it should cost less than a year's pay for the average American. While not absolute constraints, those are reasonable goals.
Since a spotting scope is used by a shooter while shooting, or by a separate person acting as a spotter for a shooter in the process of shooting, one hard constraint, I would think, would be that the scope have enough eye relief to be used at all magnifications while wearing glasses (you're never supposed to shoot, or be with a shooter, without those safety glasses, right?).
Yet that eliminates the majority of "spotting scopes" on the market, right there in one fell swoop. I have looked at entire inventories in more than one gun store and not found a single spotter that allowed me to use glasses.
Another constraint would be that the spotter's optics have better resolution than that of the gun sight. This one gets more personal, or situational. If you're using a high quality 20x riflescope, you're going to want a higher quality spotter, probably with more magnification. Otherwise you can "spot" using your riflescope.
You have no use for a separate optic unless it can resolve as well or better than your gunsight.
If you're using iron sights, your spotter will still need to detect mirage and see bullet holes.
If you're shooting at 100 yards or less, probably the cheapest of the cheap scopes will do-- except that they never seem to have the eye relief to use them without violating range rules regarding eye protection. May as well use a medium quality pair of 8x or 10x binoculars-- they're more versatile anyway. At 100 yards with a decent 8x rifle scope, you can see your bullet holes, down to 22 caliber, just fine. You don't need to dope wind at 100, so you don't need a spotting scope unless your sight has less than about 8x magnification or is of poor quality (but then why buy a poor quality rifle scope and a poor quality spotting scope, when you could just get one good riflescope). Once you get out to 200, 300 and especially beyond 300, you need some pretty good optics. Otherwise don't even think about seeing bullet holes. This is where a spotting scope comes in, no matter what, and it has to be a good one.
Then there are the scope stands. I've tried camera tripods and the little 6" thingies that come with cheap spotting scopes. Very cumbersome. A day using that setup and you're tired and a little frustrated. I got a celestial 'scope stand that has T&E (traversing and elevation) fine-tuning at the turn of a crank. Much, much better for getting on target, really nice, but the tripod configuration tends to get in your way. Serviceable, but sub optimal, plus it can't be used shooting prone when alone-- it can't get nearly low enough. So we come to the stands and adjustable heads that the Highpower shooters use. It's going to be a support base with a single, vertical pole for height adjustment that supports prone shooting and standing.
No gun store I've ever seen (or most of the on-line shooter's suppliers) has anything like that in stock. You have to get them from specialty shops. Good thing we have Google.
The choices are very few in optics, and then you need a custom stand and a custom head.
What gives, Man? Maybe the market is too small, but in that case, why is there all that unusable stuff on the market? You see it everywhere and from some pretty big name brands.
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