![]() Poor optical design can hack off the sides and you will see this clearly, if you can hold the actual binoculars in front of you. As magnification goes up, apparent brightness of the image goes down. But, to make sure you're spending your money wisely, check the shape of those exit pupils, floating there in the eyepieces: They should be flawlessly round.Īlso make sure you have access to dark skies. Interestingly, older folks may have more disposable income for the more expensive higher-power instruments. Purchasing for someone a bit younger? Have a look through our guide to the best binoculars for kids. Lower power binoculars - which tend to be smaller - usually produce larger exit pupil diameters that literally won't fit into my eyes! Take this into account if you're buying binoculars as an adult. A 12-year-old child's pupils can open much wider, to almost 8 mm. As a middle-age person, my dark-adapted eyes open to a pupil diameter of about 5 mm. The key is: Exit pupils should roughly match your eyes' pupils. Celestron SkyMaster DX 8x56 Binoculars at BHPhoto for $218.49.Two numbers separated by an "x." You can think of the "x" as "by." So, a figure like "25x70" is "25 by 70." You will see stamped right there on every pair of binoculars: 12x70, 25x100, etc. The disk of the moon is about 1/2 degree wide. If you're given just the field-width in degrees (say, 4.3 degrees), simply calculate 52 feet for each 1 degree (224ft 1000yds).įor comparison, your clenched fist held out at arm's length covers about 10 degrees of the night sky. Unless you grew up on a boat – or a spaceship – reading compass courses to avoid collisions with large ships, you'll probably find the "1,000-yard field width" number easier to visualize. It might say something like: 298ft at 1000yds, or 5.7 degrees (these are equal). When you're looking at a binoculars' specifications, you'll find one or two ways of knowing the Field of View you'd experience with that particular pair. We'll give you these in descending order of importance. Here are some basic things to look for when choosing between binoculars:Ĭomprehending a few types of numbers can help you decide which binoculars are best for your specific purposes. It's time to think about what to look for when selecting the best binoculars to meet your night sky needs. Now that we've taken a look at why you may want to choose binoculars over a telescope. Binoculars present the world in correct perspective. Some also make it "backward" - as if seen in a mirror (because that's exactly what's happening). Many telescopes show you the sky upside down. They give you a better chance to see patterns in the cosmos. And binoculars give you a much better appreciation for how objects relate to one another. ![]() Binoculars, with their wider field of view, let you scan the sky for targets. For a most fulfilling visual experience, get all your brain's "wetware" working on it. Remember, seeing occurs in your mind's eye. ![]() Binocular literally means "two eyes." You get twice the opportunity to paint your brain with starlight. It's an issue for everything, really, except the moon - which can be too bright - and a few vivid planets. That's a problem when observing deep-sky targets like comets, galaxies and widely diffuse star clusters. Paradoxically, the more a telescope magnifies an object, the dimmer that object appears. This is where binoculars have an advantage over even the best telescopes available. Binoculars can lock in tightly to both your eye sockets and your hands are close in to your face for more stability. Angling a long tube up toward the sky makes the shake problem even worse your extended arm wiggles the front objective lens. So telescopes need to sit on tripods or rocker-boxes for stability. Even little ones are bigger, heavier and longer than most binoculars. Oberwerk 15x70 Ultra Binoculars (Black) at Amazon for $149.95.(Image credit: / Jeremy Lips & Dave Brody )
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