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High-end Scopes Roundup

For this review, we surveyed an even dozen full-sized birding scopes, sent to us by manufacturers as their top-of-the-line scopes. All were full-sized scopes, with objective lenses between 77mm and 88mm, and all were of the angled-eyepiece design. They all came with zoom eyepieces: 10 scopes with the usual 20–60x zoom and two—the Leica and Swarovski—with new, wide-angle, 25–50x zoom designs. All were waterproof, and all had fully multi-coated optics and special glass to minimize chromatic aberration.

We had the scopes for more than a month, enough time to become quite familiar with them and to test and retest under varying conditions. We also invited a team of Iowa bird watchers, who were delighted at the opportunity to compare the best of the best, to come for a test day to assist in the evaluations.

Perusing the prices, you may catch yourself blinking. Can you now really spend $4,000 on a spotting scope? Indeed you can, and more than half of those in our survey cost more than $2,000. The range of prices in the 12 scopes is from $575 to $3,995.

Here's how we tested, which scopes got the top scores, and why.

Best Resolution

A primary consideration of a scope is its resolution, the ability to show fine detail. We tested all the scopes for resolution at a mid-range distance of 25 yards. We set the eyepieces to the highest power they all had in common, which was 50x. Our target was a standard United States Air Force resolution chart. We then mapped the observed relative scores to a scale in which the top score was 5.

For scopes that got similar scores, we went further. We put a booster on the eyepieces and compared them at double magnification, at 100x. Only then could we see any differences in resolution among some of the top scopes. As another test, we placed a one-dollar bill next to the chart so we could compare text, graphics, and fine engraving details.