From the September 2004 issue

I have quickly come to find out that my 3.5-inch refractor is completely useless on faint objects, such as nebulae, galaxies, globular clusters, and comets. Will they be well within my reach with an 8-inch telescope?

Scott Tierce, Dallas, Georgia
By | Published: September 1, 2004
Scope sketches
You have already learned one of the fundamental lessons about telescopes: Size rules. The larger the diameter of the telescope (the kind of scope doesn’t matter), the more light it will collect. A 3.5-inch refractor is a good scope for planets, the Moon, and double stars. I know because I own a 4-inch refractor, and I wouldn’t part with it for love or money. But this size telescope is a bit small for deep-sky objects such as nebulae and galaxies. Things improve if you can get away from city lights and observe under a really dark sky, but size remains a limiting factor.
An 8-inch telescope (again, it doesn’t matter what type) will move you into a new dimension of viewing. The objects you now observe with your 3.5-inch scope will show much more detail in an 8-inch scope, and they’ll be quite a bit brighter.

Let me mention a specific note about observing galaxies. These objects are quite low in surface brightness, so you’ll want to observe from a dark site to increase their contrast with the sky.

And here’s another thing to keep in mind: If you stay interested in observing, someday you’ll probably want an even larger scope. This malady among amateur astronomers is known as “aperture fever,” and, yes, I’m infected. I started many years ago with a 2.4-inch telescope of good quality. I now own a 4-inch refractor and a 12-inch Schmidt-Cassegrain, and I dream of owning a 20-inch telescope. — MICHAEL E. BAKICH, ASSOCIATE EDITOR

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