Brand
Explore Scientific occupies an unusual position: genuinely good apochromatic refractors at prices below the premium brands, and Ritchey-Chretien astrographs at prices that make long focal length accessible to people who would otherwise never own it. Both product lines reward buyers who know what they are getting into, and both have caught out buyers who did not. We are not affiliated with Explore Scientific and this page is not endorsed by them.
Go2Telescope is independent. We are not affiliated with, endorsed by or sponsored byExplore Scientific, and this page is our own assessment.
The apochromatic refractors are the easy ones. Sealed, collimation-free, sharp, and usable the moment they are outside. The main thing to check is that your mount has genuine margin — a 102 mm triplet is 4.5 kg on a 730 mm lever, which is more demanding than the weight alone implies.
The Ritchey-Chretiens are the opposite. Optically they deliver something no refractor at the price can — 1 600 mm of coma-free focal length — and mechanically they ask you to learn precise collimation of two hyperbolic mirrors. Owners who do this rate them very highly. Owners who do not tend to sell them and blame the design.
Buy the refractor if you want a telescope that works.
Buy the Ritchey-Chretien if you want galaxy image scale on a budget and you are prepared to treat collimation as a skill to acquire rather than a chore to avoid. Read the Ritchey-Chretien type page before ordering, not after.
We have no relationship with Explore Scientific. Where we link to a retailer we may earn a commission, which does not affect what appears here.
Ritchey-ChretienOTA only
The cheapest honest route to real galaxy image scale, provided you accept that collimating a Ritchey-Chretien is a skill you will have to acquire.
Apochromatic refractorOTA only
The classic do-everything four-inch apo: excellent visually, capable on nebulae with a flattener, and never the cheapest way to any single goal.