![]() ![]() ![]() Many stargazers have had a similar experience with small instruments. I carried that scope on its spindly tripod around the backyard, dodging swarms of mosquitos, and peering through gaps in the tree branches to surf the star clouds of Sagittarius, glimpse the polar caps of Mars and the rings of Saturn, marvel at the continuous dance of Jupiter's four big moons, and get a handle on the basic geography of our own Moon. Back in the mid-1970s, I started with a 3-inch telescope, a Tasco reflector rather than a refractor, which kept me busy and captivated for years as I learned the ropes of stargazing. There's also, at least for me, the nostalgia factor. Even brighter and larger deep-sky objects such as the Orion and Lagoon nebulae, especially in dark sky,snap into view with astonishing contrast with an appearance that's hard to equal in a larger telescope. Shadows and darker features on the Moon appear finely etched against a bone-white background. The star images are beautifully small and sharp, with classic diffraction rings enveloping each as if rendered in an undergraduate optics textbook. Then there's the superb contrast that a refractor affords for visual observers, the so-called 'refractor experience', especially with instruments with a good ED or apochromatic objective lens. You can look across the galaxy at the Pleiades or the Orion Nebula, or across the yard at a bluejay or family of robins feeding their young on a spring afternoon. It's also easy to use and requires no optical alignment. A small refractor is lightweight, just five or ten pounds, ideal for grab-and-go observing on a simple alt-azimuth mount. If you've ever tried to assemble an 18-inch Dobsonian on a cold and breezy winter night, the merits of a small refractor, one with an aperture of about 75-85mm, give or take, become clear in a hurry.įirst, there are the obvious advantages. It also involves the psychological inertia of setting up such an instrument. And it gives you larger (if not brighter) images of extended objects such as galaxies and nebulae.īut larger aperture means a bigger, heavier telescope and longer set-up and cool down time. It enables higher resolution which lets you see sharper and finer detail, and which is especially important for observing the Moon and planets. A telescope with a larger aperture collects more light and therefore gives brighter star images. Why a small refractor? When it comes to telescopes, after all, physics tells us that bigger is better. ![]() I even enjoyed a peek through the 100" Dupont telescope at Las Campanas Observatory in northern Chile when I was a graduate student in the late 1980s.īut after all these years, and despite the availability of large and reasonably-priced Newtonians and compound reflectors, there's one type of telescope I turn to most often for visual observing: the small refractor. I nearly fell off a ladder at the incredible sight of the Veil Nebula through a 25" Dob in pristine sky at a summer star party in the Adirondacks. I once caught a glimpse of a gravitationally-lensed galaxy in a 30" reflector on a transparent autumn night. I've looked through quite a few big telescopes since I took up stargazing as a youngster back in the early 1970s.
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