My 8-inch Travelscope


Have scope, will travel! This Dobsonian not only gives great views, it also fits into an airplane’s overhead storage compartment.

One of the best reasons for learning to build telescopes is that you can make instruments that perfectly match a particular observing need or circumstance. As an editor at Sky & Telescope, my “circumstance” happily involved a lot of travel, and as a result I found myself dreaming of a telescope that I could take with me as I zig-zagged across North America from one star party to the next. It seemed a shame to arrive under the dark skies of the Texas Star Party or Mount Kobau without a telescope of my own.
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My First Telescope

Tasco 3TE-R

Every stargazer has a “first telescope” story. Here’s mine.

Like many backyard astronomers, one question I get asked all the time is “When did you get interested in the stars?” The truth is, I can’t remember a time when I wasn’t drawn to the night sky. Maybe part of the reason was that my family lived on an orchard under a splendid, dark rural sky. For me, the stars were as much a part of nature as the birds in the trees and the bugs crawling on the ground.
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Save Your Scope!

Scope cover

With star-party season upon us once again, you’re probably confronting the age-old problem of how to protect your prized telescope from the triple threat of dust, rain, and heat. The traditional big, ugly trash bag or blue tarp works for two of those three (dust and rain), but looks bad and lets your scope to get way too toasty on a hot summer’s day. Alternatively, you can plunk down $50 or so on a proper dust cover, but if you’re like me, that cash almost always seems to go towards another eyepiece instead. Stumped? Don’t worry — a cheap, effective telescope cover is only as far away as your local hardware/camping-supply store.
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A Simple Double-Plate Mirror Cell for Your Reflector

Mirror cell

Remounting your Newtonian reflector’s primary mirror could lead to better performance and easier collimation.

Many telescopes have mirror mounts that are less than ideal. Some hold the mirror in place with clips that project over its surface and introduce image-harming diffraction effects. Others have adjustments that require tools or are so frustrating that observers rarely attempt to properly collimate the optics. Some cells effectively seal the mirror from the outside air. With no provision for ventilation, it is virtually impossible for the primary to cool down to the ambient air temperature — crucial for sharp images. Some mirror cells have all these problems!
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Rating Binoculars

Binos aplenty

A bewildering assortment of binoculars awaits at your local camera store. But when it comes to stargazing, some binos are better than others.

Binoculars come in a dazzling variety of magnifications and sizes. Many stargazers recommend 10x50s — binoculars that magnify 10x and have 50-millimeter-diameter objective lenses. A trip to your local camera store will likely show you a bewildering array of additional choices. You’ll see 15x70s, 8x40s, 7x35s, and so on. But how do we decide which combination of magnification and aperture is best for stargazing?
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Understanding Binocular Exit Pupils

Exit pupils

Do binoculars with small exit pupils really produce dimmer images?

One binocular specification that seems to generate more than its share of contradictory advice is exit-pupil size. I’ve often seen statements to the effect that you should avoid binoculars with smaller exit pupils because the view is “dimmer” than in models having larger exit pupils. But is this actually true, and more importantly, should it factor into your binocular selection?
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Gearing Up for a Moon Shot

Moon shot

Taking your own trip to the Moon doesn’t require anything as big and expensive as a Saturn V rocket, but a little equipment will definitely make the voyage more rewarding.

The Moon is unquestionably one of the most appealing sky sights. We’re drawn to it as though some primitive impulse from deep within rises to the surface whenever we see the lunar disk shining from the darkness, like consciousness itself. And it’s simply beautiful. No wonder it’s the subject of countless poems, the lead player in numerous nursery rhymes, and usually the very first target for a beginner’s telescope.
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