A big mirror on a box that costs almost nothing
A Dobsonian is a Newtonian reflector on a simple rocker box that swings left and right and tips up and down, and the reason it dominates the large-aperture end of the market is arithmetic: the mount costs a fraction of an equatorial head of the same capacity, so the whole budget goes into the mirror. The result is the most light any amateur is likely to buy for a given sum. What has to be read is the base, because it is the part that decides whether the telescope is pleasant. Bearings that are too stiff make fine pointing a fight; bearings that are too loose let a heavy eyepiece tip the tube. Several makers now fit an adjustable tension clutch, and that single feature changes the instrument more than a small difference in aperture would. The second question is transport: a Dobsonian separates into a tube and a base, and the honest figure is the weight of the heavier half, not the total. A truss or collapsible design shortens the tube for the car and adds a shroud and a setup routine; a solid tube stays aligned better and takes the space it takes. Height at the eyepiece matters too — a long tube pointed near the zenith puts the eyepiece where a standing adult reaches it, and a short one puts it where a chair is needed. We compare aperture, focal length and ratio, base and bearing design, tube construction, heaviest single part and eyepiece height.
130 mm parabolic mirror · tabletop Dobsonian
A 130 mm parabolic Newtonian on a manual tabletop Dobsonian base with Teflon bearings, steered by the maker’s smartphone sky-recognition app.
Best for: A beginner with somewhere solid to stand it who wants aperture without a tripod
≈ $430 / £299 / €400
130 mm parabolic mirror · 650 mm focal length
A 130/650 parabolic Newtonian on a wooden tabletop Dobsonian base, with a collapsible tube, a red dot finder and two eyepieces.
Best for: Somebody who wants a real 130 mm mirror that stores in a cupboard
≈ £264 / €273
203 mm aperture · 1200 mm focal length
A 203/1200 Newtonian on a Dobsonian base — the largest aperture in this group, sold with an accessory set and a mount with nothing to align.
Best for: The observer who has decided that aperture matters more than portability
≈ €529
76 mm aperture · 350 mm focal length
A 76/350 tabletop Dobsonian sold pre-assembled, with two eyepieces, a Barlow and a Moon filter.
Best for: A very compact first telescope for a child or a small flat
≈ £113 / €142
Any figure written into the body of this page was true on the day it was written. The amount shown next to each instrument is requested from the retailer as the page loads, and it is that amount, not the text, that stands.
