Telescope Reviews: Large binoculars for distant terrestrial objects

Well, Doc, there are some interesting observations here....one thing to consider tho'...you mentioned looking across considerable expanses of land & water. In the daytime, frequently there is considerable heating or cooling of the air (what the meteorologists call heating-degree or cooling-degree minutes). This in turn causes thermal activity, which causes the kind of shimmering "funhouse effect" to the image that you see in the movies when a scene is filmed in the desert...the higher the magnification, the more pronounced it is. I currently have 4 hi-end binos and a premium scope and do a lot of birding by local lakes. I find that very seldom can I use the really hi-power eyepieces on the scope and often even the stronger binos don't work as well as the lower powered ones when there is several degrees difference between the air temp and that of the water surface, or between air temp at ground level and just up a few meters. Air has to very stable to have good seeing conditions if you're talking about looking at something much over 2-3 miles away and seeing it to best advantage. I can only use the highest power eyepiece on my scope (48x) very seldom and get the kind of image it's capable of producing...usually the lowest pwr ep (24x) will give a cleaner, more usable view with just as much detail, just a smaller image. This is one of the problems of terrestrial viewing vs cosmological....when stargazing you're looking thru much less dense air which isnt as susceptible to thermal currents, tho' there can be some. Now, having said that, your first-mentioned choices of a Celestron or Oberwerk 15x70 are really close to the mark. Haven't had a chance to try the Obie, but can tell you 1st hand that the Skymaster is one the absolute steals in hi-pwr optics out there. A friend just got one from Christopher's (Astronomics) and we gave it the acid test against the other stuff we had on hand, and it aquits itself very well, indeed....and for $89! The afov is 66*, which gives a true picture-window image, has enough eye relief with the cups down to use glasses with no vignetting, and with the supplied tripod adaptor on a good mount, will resolve car tags across a vacant field in a parking lot at a measured distance of almost 530 meters..about 1/3 of a mile. It's certainly not perfect (has a little field curvature and mild edge softness) but for the $, it's untouchable in that end of the bino power spectrum. Based on my experience with the Oberwerk 20x80, I doubt their 15x70 will perform as well as the Celestron but I could be mistaken. All in all, I think
you'd be very satisfied with the Celestron, plus wd have enuf left over out of yr $300 limit for a good 7-8x wide field glass (a B&L 8x40 Legacy or similar) to really give you viewing versatility. Later, if you find that in yr area the atmospheric thermal actvity isn't all that severe, you cd get a good scope and still not have a small fortune invested (you can get a very good one with a couple of fine ep's for around $750-800). My several cts worth, based on a lotta years of viewing thru a lot of glass...hope this will be useful in yr decision.