# AstronomyTested > Telescope and astronomy guides: refractors, reflectors, Dobsonians, smart telescopes, mounts, eyepieces, filters, astrophotography cameras and binoculars, with beginner, intermediate and advanced paths. AstronomyTested publishes telescopes and astronomy gear reviews, buying guides and reader discount codes. Every review states who the product suits, the current price from the brand's own store, and any active reader code. ## Key pages - [Reviews](https://astronomytested.com/reviews): every product we recommend - [Buying guides](https://astronomytested.com/guides): how to choose - [Glossary](https://astronomytested.com/glossary): telescopes and astronomy gear terms defined - [How we test](https://astronomytested.com/testing-methodology) ## Topics - [Telescopes](https://astronomytested.com/category/telescopes): Refractors, Newtonian reflectors, Dobsonians and catadioptric telescopes. - [Smart telescopes](https://astronomytested.com/category/smart-telescopes): All-in-one smart telescopes that image and stack automatically. - [Mounts & eyepieces](https://astronomytested.com/category/mounts-eyepieces): Equatorial and alt-azimuth mounts, star trackers, eyepieces, Barlows and filters. - [Imaging & observing](https://astronomytested.com/category/imaging-observing): Astrophotography cameras, guiding, binoculars, solar filters and observing accessories. - [Accessories & power](https://astronomytested.com/category/accessories): Tripods and piers, cases, power supplies, dew heaters, collimation tools and alignment aids. - [Beginners & education](https://astronomytested.com/category/beginners): Beginner kits, star charts, apps and educational equipment for families and first-time observers. ## Buying guides - [Equatorial vs Alt-Azimuth Telescope Mounts](https://astronomytested.com/guides/equatorial-vs-alt-azimuth-mount): Alt-azimuth mounts move up-down and left-right, are intuitive and quick to set up, and suit visual observing. Equatorial mounts are aligned to the celestial pole, so tracking needs only one axis; that makes them the standard for long-exposure astrophotography. GoTo versions of either point to objects automatically. For imaging, many astrophotographers keep the load to about half of the rated payload. - [How to View the Sun Safely: Solar Filters and Eclipse Glasses](https://astronomytested.com/guides/how-to-view-the-sun-safely): Never look at the Sun through binoculars, a telescope or camera without a certified solar filter covering the front of the optics. For direct viewing, use eclipse glasses or viewers that meet ISO 12312-2 from a reputable supplier. Telescopes need a front-mounted white-light filter or a dedicated hydrogen-alpha solar telescope. Cover or remove the finderscope, and never use screw-in eyepiece solar filters. - [Refractor vs Reflector vs Catadioptric Telescopes Compared](https://astronomytested.com/guides/refractor-vs-reflector-vs-catadioptric): Refractors use lenses, need little maintenance and give sharp, high-contrast views, but large apertures get expensive. Reflectors use mirrors and give the most aperture for the money, especially as Dobsonians, but need occasional collimation. Catadioptrics such as Schmidt-Cassegrains and Maksutovs fold a long focal length into a short tube, suiting the Moon, planets and portable setups. Aperture, mount and where you observe matter more than type. - [Smart Telescopes Explained: What They Do and What They Can't](https://astronomytested.com/guides/smart-telescopes-explained): Smart telescopes combine a small telescope, a camera and a computerized mount, controlled from a phone. They find objects automatically and build up color images by live stacking many short exposures, even from suburbs. You look at a screen rather than through an eyepiece. Small apertures limit planetary detail, and images take minutes to develop, but they make deep-sky imaging far easier. - [Telescope Aperture and Magnification Explained](https://astronomytested.com/guides/telescope-aperture-and-magnification-explained): Aperture, the diameter of the main lens or mirror, sets how much light a telescope gathers and how fine a detail it can resolve. Magnification is just the telescope's focal length divided by the eyepiece's. The maximum useful magnification is about 50 times per inch of aperture (2 times per millimeter), and steady air rarely allows more than about 250 to 300 times. Ignore boxes that advertise huge magnification. - [Telescope Eyepiece Guide: Focal Length, Field of View and Eye Relief](https://astronomytested.com/guides/telescope-eyepiece-guide): Build an eyepiece set around three jobs: a low-power eyepiece for finding objects and wide views, a medium one for most deep-sky viewing, and a high-power one for the Moon and planets. Magnification is telescope focal length divided by eyepiece focal length; true field is apparent field divided by magnification. Choose 15 mm or more of eye relief if you wear glasses, and match barrel size (1.25 or 2 inch) to your focuser. Contact: info@astronomytested.com