Ranking UK's Best & All 93 Astronomy Binoculars

Understanding Binocular Specs

In astronomy, it is often desirable to be able to observe faint objects such as distant galaxies, nebulae, and star clusters. These objects can be difficult to see with the naked eye, and require a telescope or binoculars with good light-gathering ability to be visible. Binoculars with a smaller aperture may not be able to collect enough light to make these faint objects visible, making them a less effective tool for astronomy. Aperture is generally referred to in millimeters, and useful astronomy binoculars range from 35mm to as large as 152mm in aperture, though usually, they are between 35mm and 80mm.

Binoculars under 35mm aperture are useless for astronomy as they lack sufficient light-gathering power to reveal much more than your naked eye, and thus present disappointingly dim views.

In general, astronomy binoculars should have a magnification between 7x and 25x in order to provide a good balance between image detail, stability, sharpness, and field of view. At higher magnifications, the view through binoculars will appear larger, but the field of view will be narrower. This can make it more difficult to locate and observe celestial objects, as you will see less of the sky at once. Additionally, higher magnifications are more sensitive to shaking from your hands or an inadequate mounting, bring out flaws in optical quality and collimation with many binoculars, and generally belong to the domain of telescopes.

Above 12x magnification or so is generally when you’ll need a tripod for your binoculars in order to allow for sufficient aiming accuracy and provide a steady platform; some people have trouble holding anything above 8x steady enough, and stronger people may be able to handle 15x binoculars for handheld use, but generally, most users’ limit to comfortably observe with handheld binoculars will be around 10-12x.

Binoculars are generally referred to by their magnification followed by the aperture. A 7x35 binocular has a magnification of 7x and a 35mm aperture, while a 12x70 binocular has a magnification of 12x and 70mm of aperture.

Porro prisms and roof prisms are the two different designs used in binoculars to invert the image so that it is right-side-up and left-to-right correct.

Porro prisms are a traditional design that uses two prisms arranged at a right angle to each other to deflect and invert the image. They are named after the Italian optician Ignazio Porro, who patented the design in the 19th century. Porro prism binoculars are characterized by a distinctive zig-zag shape, with the objective lenses offset from the eyepieces.

Roof prisms, on the other hand, use a single prism with a roof-shaped cross-section to invert the image. They are generally more compact and lightweight than Porro prism binoculars and are often used in compact or travel-sized binoculars.

One advantage of Porro prisms for astronomy binoculars is that they tend to have a wider field of view compared to roof prisms of the same magnification and objective lens size. This can make them more convenient for observing celestial objects, as they allow you to see more of the sky at once. Additionally, Porro prisms may offer better image quality and contrast due to their less complex optical design, especially when comparing two binoculars at the same price point.

However, it is important to note that the choice between Porro and roof prisms in binoculars is not always a simple matter of one being inherently better than the other. Both designs have their own strengths and weaknesses, and the best choice will depend on the specific needs and preferences of the user.

BK-7 and BaK-4 are the two commonly seen types of glass used in the prisms of binoculars.

BK-7 glass is a type of borosilicate crown glass that is commonly used in the prisms of lower-cost binoculars. It is relatively inexpensive and has good transmission properties, but it is not as dense as some other types of glass and may not offer the same level of performance in terms of image quality and clarity. BaK-4 glass, on the other hand, is a higher quality glass that is denser and more optically pure than BK-7 glass. It is often used in the prisms of higher-end binoculars because it offers better image quality and clarity.

In astronomy binoculars, the quality of the prisms can be an important factor because it affects the overall image quality and clarity of the instrument. BaK-4 prisms are generally considered to be a better choice for astronomy binoculars because they offer better image quality and clarity compared to BK-7 prisms. We usually recommend purchasing binoculars with BaK-4 prisms. Many cheap binoculars use BK-7 prisms which are also undersized and vignette the aperture of the objective lenses, bringing down performance.

ED glass is sometimes used in binoculars to provide additional chromatic aberration control, similar to a high-quality apochromatic refractor telescope. However, at the low and usually fixed magnifications offered by all but the largest astronomy binoculars, you are unlikely to benefit much from spending additional money on ED glass alone; other features are more important.

Binoculars typically have eyepieces with apparent fields of view of 50 degrees (similar to a Plossl or Kellner telescope eyepiece) or greater. Wide-angle eyepieces can be more immersive but are harder to manufacture to a high standard of quality. The apparent field of binoculars combined with their magnification dictates the true field, as with a telescope. A good pair of 7x or 10x binoculars have a true field of view of 6.5 degrees of greater. Binoculars with a true field of under 4 degrees are very hard to aim.

Features to Avoid

Zoom binoculars tend to have lower image quality compared to fixed-magnification binoculars. This is because the additional moving parts and lenses required for the zoom feature can introduce distortions and aberrations into the image. Additionally, zoom binoculars often have a narrower field of view and less light-gathering ability than fixed magnification binoculars, which can make it more difficult to locate and observe objects. The high magnifications offered are rarely of any use, being too shaky to use handheld, and if you’re bothering with a steady mount and tripod, a telescope is a better choice. Another issue with zoom binoculars is that they are generally less durable and more prone to failure than fixed-magnification binoculars. The additional moving parts in zoom binoculars can be prone to wear and tear and may require more frequent repairs or maintenance.

“Ruby-coated lenses” are often used to block out certain wavelengths of light to hide shoddy optical quality in binoculars. This reduces light-gathering ability and is also a general indication of a low-quality unit to begin with. Avoid any binoculars with such claims, even for non-astronomical use.

Binoculars with an aperture smaller than 35mm should be avoided due to both quality concerns in lower-priced units and the lack of capabilities offered by such smaller apertures.

“Perma focus” and other similarly advertised binoculars are an attempt to sell low-quality units that lack a focus mechanism as somehow advantageous. They are essentially a scam; avoid them.

Under £75

Visionary 7x50 High Definition

Best Performance

Rank 1

4.4_^/5

The Visionary 7x50s are a splendid set of binoculars that punch well above their weight and price category. Their multicoated optics are particularly impressive, as they excel at providing stunning views of a diverse array of celestial objects. The inclusion of high-quality BAK-4 prisms is another noteworthy feature; these prisms are integral in producing sharp and high-contrast images. These binoculars boast a 7-degree field of view, which is remarkably sharp, with only a minor softening towards the outer 5-10% of the field. This is a small compromise, given the outstanding performance and image quality in the central portion. Whether you’re a seasoned astronomer or just dipping your toes into the wonders of the night sky, the Visionary 7x50s are a fantastic investment.

Rank	Telescope	Rating
Rank 8	Pentax Jupiter 10x50	4.2
Rank 9	Visionary 7x50 Classic Binoculars	4.1
Rank 10	Opticron 30189 Oregon WA 10x50	4
Rank 11	Bresser Binoculars 7x50 Porro	4
Rank 12	Bresser Travel Binoculars 7x50	4
Rank 13	Levenhuk Atom 7x50 Ultra-Compact Binocular	4
Rank 14	Bresser Binoculars Hunter 7x50	4
Rank 15	DANMO 10x50 Binoculars for Adults	4

Rank	Telescope	Rating
Rank 16	Praktica Falcon 7x50 Binoculars	3.9
Rank 17	Bushnell PowerView 10x50	3.9
Rank 18	Sotae 10x50s	3.9
Rank 19	Opticron Oregon WA 8x40 Binocular	3.9
Rank 20	Pentax Jupiter 8x40	3.9
Rank 21	Tasco 10x50	3.9
Rank 22	Bushnell Falcon 10x50	3.9
Rank 23	Celestron UpClose 10×50	3.9
Rank 24	Celestron Outland X 10x42 Binoculars	3.9
Rank 25	Pentax Jupiter 12x50	3.9
Rank 26	Bushnell PowerView 12x50	3.9
Rank 27	Celestron Cavalry 10x50	3.8
Rank 28	Celestron UpClose G2 8x40	3.8
Rank 29	Celestron UpClose G2 7x35	3.8
Rank 30	Bushell Falcon 7x35	3.8
Rank 31	BARSKA Crush Series 10x42	3.7
Rank 32	Celestron LandScout 7x35mm Porro	3.5
Rank 33	Bushnell PowerView 20x50	3.4
Rank 34	Celestron UpClose 20x50	3.4

Rank	Telescope	Rating
Rank 35	Pentax Jupiter 16x50	3.3
Rank 36	Visionary Black 7x50 Marine Focus Free Waterproof Binoculars	3.3
Rank 37	Visionary YELLOW 7x50 Marine Focus Free Waterproof Binoculars	3.3
Rank 38	Konus Konusvue 7X50 Binocular	3.3
Rank 39	Konus 7x50 Sporty Fix Focus Binoculars	3.3
Rank 40	Celestron UpClose G2 10-30x50 Zoom	3.3
Rank 41	Celestron Outland X 8x25	3.2
Rank 42	Celestron UpClose G2 10x25	3.1
Rank 43	Celestron Up-Close G2 8x21 Roof	3.1
Rank 44	Celestron LandScout 10x25 Roof	3
Rank 45	Celestron Kids 4x30	2.5

Rank	Telescope	Rating
Rank 1	Barska Waterproof Blackhawk 10x42	3.9
Rank 2	Celestron SkyMaster 25x70	3.9
Rank 3	Barska Waterproof Blackhawk 12x42	3.9
Rank 4	Nikon 8244 ACULON A211 7x35	3.9
Rank 5	Celestron Ultima 8x32	3.9