Choosing your first telescope: an honest beginner's guide

The fastest way to put someone off astronomy is to give them a bad first telescope. The internet is flooded with them. Cheap refractors boasting “600x magnification!” on the box, with tripods so wobbly you can’t keep Jupiter in the eyepiece for more than three seconds. They disappoint. The new owner concludes they aren’t cut out for this, puts the scope away, and never tries again.

This guide exists to save you from that. Including the case for not buying a telescope at all yet.

Consider binoculars first

Before anything else: a decent pair of binoculars will beat a bad telescope every time, and cost a fraction as much.

Binoculars in the 7x50 or 10x50 range (first number is magnification, second is aperture in millimetres) are genuine astronomy instruments. With them, you can see:

• Craters of the moon in detail
• The four Galilean moons of Jupiter
• The phases of Venus
• Dozens of star clusters, including the Pleiades in full splendour
• The Andromeda Galaxy as an unmistakable elongated glow
• Countless double stars and rich star fields in the Milky Way

A well-reviewed 10x50 costs roughly $70 to $150 new. They’re also portable, work for birdwatching during the day, and impossible to “break” with a wrong mount. For many people, binoculars are all the astronomy gear they’ll ever need.

If you buy binoculars and use them happily for six months before wanting more, you’re ready for a telescope. If they end up in a drawer after two weeks, you’ve saved yourself a much bigger, more awkward purchase.

The one number that matters: aperture

If you do buy a telescope, aperture matters more than anything else.

Aperture is the diameter of the main light-gathering element: the lens (for refractors) or the mirror (for reflectors). Bigger aperture equals more light gathered equals more detail visible.

Magnification is nearly irrelevant as a spec. Any telescope can be set to any magnification by swapping eyepieces. The real question is: at high magnification, does the image hold up? That depends on aperture and optical quality. Cheap telescopes advertised at “525x magnification” are marketing fiction. At that magnification on a small aperture, the image is a blur.

A rough rule: useful magnification tops out at about 2x the aperture in millimetres. A 150mm scope gives good views at 300x. A 60mm scope starts falling apart above 120x.

The three telescope types

Refractors use a lens at the front. The thing most people picture when they think “telescope.” Simple, easy to maintain, hold alignment well. But per millimetre of aperture, they’re the most expensive type. Good refractors of useful size (80mm or more) start around $300.

Reflectors use a mirror at the bottom of the tube. You get far more aperture for your money. A 150mm (6-inch) reflector is affordable and capable. The mirror occasionally needs alignment, which beginners sometimes find fiddly, but the process is quick to learn.

Compound telescopes (Schmidt-Cassegrain and Maksutov designs) use both a mirror and a lens. Compact for their aperture, often with computer-controlled mounts. Excellent but expensive.

For a first scope, the best value is a Dobsonian reflector. A large-aperture reflector on a simple, rock-stable base. Dobsonians are designed for visual beginners. Cheap per millimetre of aperture, almost impossible to knock out of alignment, and the mount is so simple that setup is under two minutes.

What to actually buy (USD)

Under $200: skip the telescope, get binoculars. A 10x50 pair plus a beginner astronomy book is a much better use of the money.

$300 to $500: the sweet spot. A 6-inch (150mm) Dobsonian reflector. Sold by Orion, Sky-Watcher, Celestron, Zhumell. Shows Jupiter with its belts, Saturn with rings, dozens of galaxies and nebulae.

$500 to $900: an 8-inch Dobsonian. Meaningful upgrade. Shows globular clusters resolving into individual stars, faint galaxies clearly, serious planetary detail.

$1000 and up: specialised equipment. Goto mounts, astrophotography setups, apochromatic refractors. Only relevant when you know what you want.

What to avoid: any telescope from a toy store or general-purpose retailer that advertises magnification as its headline spec. Plastic focusers. Wobbly tripods. “Bonus accessory packs” that substitute for optical quality.

What you’ll actually see

The most common source of disappointment is expecting Hubble-style images through an eyepiece. You won’t get that. Ever. Photographs online are long exposures processed from many frames. Through an eyepiece, you see what your eye sees in real time.

Through a good 150mm telescope, this is the honest experience:

Moon. Stunning. Craters, mountains, rays, fine detail along the lunar terminator. The single most impressive target for any telescope.

Jupiter. A small bright disk with two or three dark cloud belts, and four tiny points of light on either side. Those are the Galilean moons.

Saturn. Small but unmistakable. A disk with a ring clearly separated from it. Seeing Saturn’s rings with your own eye for the first time is the moment most beginners get converted for life.

Mars. A small orange disk, sometimes with a polar cap visible.

Orion Nebula. A genuinely beautiful cloud of glowing gas with four young stars at its heart.

Galaxies. Faint, elongated smudges. Not colourful spirals. Still moving, because those are galaxies.

None of this is Hubble. All of it is photons that left those objects years, decades, or millions of years ago, now arriving on your retina. Worth more than any saturated screenshot.

Before you buy anything

Learn the sky with your naked eye first. Buy a planisphere, or use a free app like Stellarium. Spend a month just knowing where the constellations are and when the planets are up. By the time you feel ready to invest in a telescope, you’ll know exactly what you want to see. Which means you’ll know which telescope to buy.

A telescope you’ll actually use is always better than a more capable one that lives in a cupboard. Start simple. Grow as you grow. Nothing about astronomy rewards rushing.