Be it a concert, the Kentucky Derby, a political rally, football game or the opera, spectator binoculars can come in handy for just about any occasion where getting a closer view of an event is needed. Usually compact, portable, and elegant, spectator binoculars are designed to fit in a pocket, handbag, or messenger bag, and are easily portable. They do not need to be as robust or specialized as their hunting, birding or marine cousins, although the basic principles behind them remain the same.
Like every other pair of binoculars, spectator binoculars consist of two identical, mirror-symmetrical telescopes placed side-by-side and aligned together. This arrangement grants observers an incredible depth of field and magnification while retaining the eye’s ability to see objects in three dimensions, something which a monocular telescope is unable to do.
For most people, a pair of wide angle compact binoculars with magnifications levels that range from 6x to 7x and objective lens sizes ranging from 25mm to 40mm should suffice. Binoculars in this size range are normally lightweight, stable and easy to hold over long periods of time. If you know you are likely to be seated, a set of binoculars with a magnification of 10x will provide a crisp, close-up image of what you are trying to view. Try not to go above 10x, as it will cause the image to suffer.
This occurs because of a basic tenet of optical imaging - the higher the magnification of the binoculars, the further the distance visible. However, as you zoom progressively closer, the field of view becomes more restricted as light is denied access to the lenses, and the image may not be quite as clear as a lower magnification could provide. Finding a happy medium is therefore a key part of choosing a good pair of spectator binoculars – hence the recommendation of anything between 6x-10x, but no greater.
more advanced, you can begin to worry about things like magnification compared to objective lens size. Objective lens size is a fairly simple choice to make - the larger the lens, the more light will be collected and the sharper the final image will be. However, large lenses also tend to lead to bulkier construction, and can be less manageable.
The best advice is to use your own common sense and judgment – how far away will you be from the stage? In a standard concert hall, 10x magnification will probably be overkill. But if you were stood at the back of the crowd at, say, President Obama’s inauguration, then you may need the boost to the viewing distance that a larger pair of binoculars can provide.
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