While most astronomers tend to favor the scientific telescope for amateur astronomy and stargazing, a growing number of people are breaking in to the hobby by using a pair of binoculars to observe the Earth’s closest celestial neighbors. More portable than a telescope, cheaper, and often far easier to use, binoculars can be a very attractive alternative to the common-or-garden telescope, particularly among more physically active astronomers.
Made from two identical, mirror-symmetrical telescopes placed side-by-side and aligned together, binoculars grant hunters 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.
Unless you are dead certain that the investment is worth it and that your interest in the hobby isn’t going to fade after a few weeks, hold off on buying a super-expensive pair of binoculars that come complete with all the bells and whistles. Instead, plump for a pair of reasonably inexpensive optics that that feature variable focus, don't weigh more than a kilogram and give a clear, sharp view. Make sure you try out the binoculars before you buy – dependent on your eyesight, a given pair of binoculars may not be the best option for you to pick.
As you get more advanced, you can begin to worry about things like magnification and 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.
Magnification and zoom require a bit more thought and consideration. The theory behind this conundrum is simple - 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, and the image may not be quite as clear as a lower magnification could provide. A high magnification is therefore not necessarily a better option, particularly for spotting game on an initial sweep of an area. Finding a happy medium is therefore a key part of choosing a good pair of hunting binoculars – many people like to combine a low-magnification, large objective lens pair of binoculars with a spotting scope for more close-up work. However, if your budget will only stretch to one of the two, go for a mid-range pair of binoculars as they are easier to manage, quicker to use, and cause less eye and neck strain.
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