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ApertureBuy the right telescope, not the biggest one

Instrument class

70–90 mm refractor on an alt-az mount

The shape most people picture when they picture a telescope. Sealed tube, nothing to collimate, and a standing eyepiece height that suits sharing.

Specifications for this class
Aperture70–90 mm
Focal ratiof/6–f/13
Typical weight5 kg
Setup time5 minutes
Learning curve2 out of 5
Price band€150–420
Useful magnification13× to 160× at 80 mm

What it does well

  • Point it and look. No collimation, ever
  • The eyepiece stays at a comfortable height wherever you aim
  • Doubles as a daytime spotting scope

What it costs you

  • 70–90 mm is not much light. Deep sky is a short list
  • Cheap achromats show a violet fringe on the Moon and bright planets
  • The bundled tripod is usually the weak part — a wobbly tripod ruins a good tube

Fit against each goal

  • Sharing it with children · 4 out of 5

    Standing height, sealed tube, and no mirror to knock out of line.

  • The Moon and the planets · 3 out of 5

    Good on the Moon and adequate on Saturn. A long focal ratio keeps the colour fringing down.

  • Learn my way around the sky · 3 out of 5

    Wide fields at low power make star-hopping straightforward.

  • Taking it with me · 3 out of 5

    Compact enough for a car; the tripod is the awkward part.

  • The Sun · 3 out of 5

    With a purpose-made front filter, a small refractor is an excellent white-light solar instrument.

  • Nebulae, clusters and galaxies, by eye · 2 out of 5

    Bright clusters and the Orion Nebula. Galaxies are mostly out of reach.

Models in this class

Indicative European street prices with the date they were observed. Ordered by price. Links marked earn us a commission and cost you nothing extra.

  • Celestron AstroMaster 70AZ

    €175seen 2026-08-17

    70 mm · 900 mm focal length · f/12.9 · 4.5 kg

    With a 10 mm eyepiece: 90×, 0.8 mm exit pupil.

    Mount Lightweight alt-az on an aluminium tripod

    Eyepieces 20 mm and 10 mm

    Listed because it is what most high-street searches return. The optics are fine for the Moon; the tripod is light enough that the image shakes for several seconds after each touch. A tabletop Dobsonian at the same price gives roughly three times the light and a steadier view.

    Where to buy

    None of these links earn us anything.

  • Celestron StarSense Explorer DX 130AZ

    €420seen 2026-08-17

    130 mm · 650 mm focal length · f/5.0 · 8 kg

    With a 10 mm eyepiece: 65×, 2.0 mm exit pupil.

    Mount Alt-az with slow motion, phone plate-solving cradle

    A Newtonian rather than a refractor, listed here because it behaves like one for the buyer: the phone finds the target and tells you where to push. Genuinely good at getting beginners onto objects without a GoTo mount's alignment routine.

    Where to buy

    None of these links earn us anything.

See whether this class suits you →