For the uncertain buyer, the man perplexed by magnification formulas and the intricacies of lenses, purchasing binoculars can be a discomforting experience. In a cramped shop he lifts the glasses to his eyes, muddles with the focusing and finds little reassurance in the blur and warp of images. "Now aren't they remarkable?" the salesman is saying. "Really superb."
Well, maybe superb and maybe not. A salesman at New York's Willoughby-Peerless, which sells as many as 300 pairs of binoculars in a week, estimates that three out of four people have no notion how to go about purchasing binoculars. At the New York headquarters of Zeiss, the prestige binocular manufacturer, a German expert declares, "People seem to believe the bigger, the better—the higher the power, the better equipped they are. That is a mistake. Often it is just the opposite."
Certain factors must be considered in the selection of binoculars: among them, the sports you will use them for, the price you can pay and even perhaps your age, health and physique. The starting point is the peculiar algebra of binoculars—3x20, 6x30, 7x42, 10x50. The first number indicates the degree of magnification: a bird viewed through the glasses will appear to be three times, six times, seven times or 10 times larger than it would to the unaided eye. The second number in the formula is the diameter in millimeters of the front lens and serves as a measure of the light-gathering quality of the binoculars. The higher this second number is the better the viewer will see in dim light, in fog and at night. The rangers on fire towers in national forests and game wardens patrolling the Everglades at twilight use 8x50 and 10x50 binoculars.
High-powered glasses, those nine-power and up, require steady hands. The slightest movement of these glasses causes jumping images. Because of this, birdwatchers using 10- and 15-power binoculars mount them on tripods. An elderly person, or one whose hands are the least bit shaky, should never use more than six-power glasses. Yachtsmen are limited in much the same way because of the pitch and motion of their boats. They find glasses over seven-power uncomfortable. What they sacrifice in magnification, however, they can pick up with good light-gathering binoculars, like 7x42s or 7x50s. These are really necessary for locating nautical markers in foul weather.
A person using 7x50 binoculars receives no special advantage in sunlight, while watching an afternoon football game, for example. Someone using glasses that size will see no better or brighter image than another using a 7x30 model. That is because the human eye adjusts, the pupil dilating in sunlight, and no matter how bright an image the binoculars pick up and transmit through the lenses, the eye will take in only a small portion of the light. At night, when the pupil grows larger and opens to its maximum, it is able to absorb the wider beam from the 7x50 glasses. Well, then, why not buy 7x50s even if your primary use is in full daylight? The answer is that because of their size, the 7x50 glasses are normally much larger and heavier than 7x30s and therefore more of a nuisance to carry.
Fred Capossela, for 36 years the race caller at New York's thoroughbred tracks, uses extraordinarily strong Zeiss 15x60 glasses but, he explains, he needs instant definition. He must be able to pick up a pink sash or a blue cap half a mile away and often through rain, fog or flying mud. "I would never recommend binoculars like that for the average racegoer," Capossela says. "For the man in the grandstand I'd suggest a more restful glass, certainly nothing any larger than 7x50."
Edward Erickson of the National Ski Patrol in Denver advocates 7x35 binoculars for use in snow country. He also suggests that amber sun caps be put over the lenses to cut the harsh intensity of light.
Among hikers, low-powered binoculars—6x30s—are popular. In part this is because compactness and lighter weight are desirable factors. Also, if the walker is tired when he uses 7- or 8-power binoculars, the image tends to bounce around crazily.
The buyer should decide before going into a store on the power and brightness he needs (7x35 glasses are recommended for the all-round sports fan) and about how much he will spend. If he is a mountain climber his glasses will knock continually against rocks and ledges, and it is wiser to purchase two cheap pairs than one expensive pair. Ordinarily, the better the binoculars the more jar they can stand, but there are limits to everything. "To test binoculars for durability you should drop them," says Werner Fallet of Zeiss, with a smile. "But, of course, no salesman will let you."
No matter how little a person intends to spend, he should ask to see Zeiss, Leitz or other top quality binoculars and compare them with the model he is planning to buy. "Take your time." Dick Cohn of Willoughby-Peerless says, "and if the salesman doesn't want to give you the time, go someplace else. Your eyes have to adapt to binoculars—like a new pair of spectacles. Some of them can strain your eyes, and the cheaper binoculars vary in quality, even among the same model. I've had people spend three hours before deciding."