Telescope

How to choose the perfect telescope for stargazing

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Nothing beats smokin’ hot summer nights for skinny-dipping and dock partying. But when it comes to stargazing, early spring is an astronomer’s friend. The air is clearer, the nights longer, and the planets and constellations more visible. And, of course, “a great opportunity to be exposed to the night sky is definitely up at the cottage,” says Ray Khan, a Manitoulin Island cottager and member of the Royal Astronomical Society of Canada for more than 30 years. To get a good look, you’ll want a good telescope. The tech is more powerful, easier to use, and less expensive than ever. Plus, astronomy is cool these days (Chris Hadfield, hello). “The hobby has come a long way,” says Khan.

There is no “best” telescope—it really depends on how you plan to use it—and there are many models to choose from (see below). Along with your interests—planets vs. nebulae vs. spying on the neighbours—“you have to consider your physical strength,” says Raminder Samra, an astronomer at Vancouver’s H.R. MacMillan Space Centre, whose personal telescope weighs 55 kg. And your level of commitment: He advises that beginners avoid clunky, complicated models that take more than 15 minutes to set up. Shop at a specialized telescope retailer, and expect to spend $200 to $300. Stay away from those with huge magnification claims—they probably aren’t any good. (Too much magnification makes the image dim and tough to see.) For each inch of aperture, there should only be magnification of about 50. Speaking of aperture, that number is key—look for a minimum of three to six inches (75 to 150 mm), depending on the design of the telescope. Don’t forget a good-quality, stable tripod, or your scope will shake in the slightest breeze.

The three main telescope designs

There are three main telescope designs, and they all work by gathering light—more than your eyeball can—and magnifying the details of the image you’re viewing.

Refractor a.k.a. refracting telescope, achromatic refractor. Bends light using lenses. Basically long, skinny tubes, refractors are the earliest telescope design.

Good: Low maintenance; durable; also useful for terrestrial viewing.

Not so good: The price is, well, astronomical if the aperture is large; less suited to viewing faint objects; can be unwieldy.

 

Reflector a.k.a. Newtonian reflector, Cassegrain, Dobsonian. Uses mirrors to gather and focus light in a design that allows for large apertures. Dobsonians, in particular, are effective scopes for amateurs.

Good: Economical; excellent for viewing distant galaxies.

Not so good: Sometimes the mirrors are dust-prone because of the scope’s open-tube design, so this type can require more care and maintenance.

 

Catadioptric a.k.a. cat, compound, Schmidt-Cassegrain, Maksutov-Cassegrain. A modern hybrid telescope that uses a mix of lenses and mirrors to form an image.

Good: Lightweight, portable, versatile, and easily hooked up to accessories such as cameras; suitable for lunar and planetary viewing.

Not so good: They can be more expensive, and moisture sensitive.