Binoculars are a low-cost way to get into astronomy without the complexity and price of a telescope or the possibility of disappointment with a wobbly or incapable instrument. However, it’s important to understand what you get when considering a pair of binoculars over a low-cost telescope. Both have advantages and disadvantages related to performance, cost-effectiveness, and versatility. It’s important to remember, also, that binoculars are simply a pair of small refracting telescopes with prisms and a fixed magnification, as well as typically being designed for handheld use.
If you don’t want to read the whole article, our conclusion (as previously mentioned in other places) is pretty simple. If your budget is under $100 USD or you don’t think you’re ready for a telescope, binoculars are far easier to learn to use, they won’t have shoddy parts or wobbly views like a bad telescope, and you can use them for purposes other than astronomy if you quit the hobby. If you’re buying a gift for someone interested in the night sky, binoculars are a low-risk investment, and you don’t really run the risk of choosing the “wrong” option like you might with a telescope. However, if you can afford a decent telescope, such as a 100mm or larger Dobsonian, the telescope is more capable in every category and will provide superior views. Don’t leave out binoculars, though – they’re so cheap and versatile that you should consider picking up a pair to accompany your telescope anyway!
We highly recommend checking out our Best Telescopes and Best Binoculars pages as well as the rankings for each to figure out what’s right for you, regardless of which option you choose to start your astronomy journey.
Without further ado, here’s a detailed summary of the pros and cons of binoculars versus telescopes, as well as what you can expect of each.
Performance
On paper, a pair of binoculars will provide you with an image that is about 1.8x brighter when you combine the view through both apertures through both eyes (though the lack of “noise”, greater comfort, etc. may provide additional performance benefits). In practice, many cheaper binoculars may have light loss from prisms being undersized, sub-optimal coatings, etc., so it may be a bit lower, more like 1.6x.
Resolution with binoculars is limited by your eye and the magnification. Your eye has a resolving power of about 1-4 arc minutes, which is amplified proportionally by the magnification of a binocular/telescope. Of course, most binoculars are low in magnification and cannot be adjusted (zoom binoculars are usually poor and should be avoided, while binocular telescopes are an expensive specialty product). This is what allows them to be made at a low cost and perform well (as well as not require a tripod, or at least a good one, for use), but also of course limits your views to the largest lunar details, the moons of Jupiter, and deep-sky objects like star clusters and some nebulae.
As such, light gathering and resolving power goes something like this:
| Optic | Effective Light Collecting Area (CM^2) | Light Gathering Vs. 114mm Reflector | Max Resolution | Resolution Vs. 114mm Reflector |
| Good 35mm Binoculars | ~17 | 22% | 34 Arcsec | 3% |
| Cheap 50mm Binoculars | ~31.5 | 40% | 24 Arcsec | 5% |
| Good 50mm/Typical 60mm Binoculars | ~35.5 | 45% | 20 Arcsec | 6% |
| Good 60mm/Typical 70mm Binoculars | ~51 | 65% | 16 Arcsec | 7% |
| High-Quality 70mm Binoculars | ~69 | 88% | 13 Arcsec | 9% |
| 60mm Refractor | ~28 | 35% | 2 Arcsec | 58% |
| 70mm Refractor/76mm Reflector | ~38.5 | 49% | 1.6 Arcsec | 66% |
| 80mm Refractor/90mm Maksutov-Cassegrain | ~50 | 64% | 1.45 Arcsec | 79% |
| 90mm Refractor/100mm Reflector | ~64 | 82% | 1.3 Arcsec | 88% |
| 100mm Refractor/114mm Reflector | ~78.5 | 100% | 1.15 Arcsec | 100% |
| 120mm Refractor/130mm Reflector | ~113 | 144% | 1 Arcsec | 115% |
| 150mm Reflector | ~162 | 206% | 0.75 Arcsec | 132% |
Binoculars above 70mm aperture are rarely cost-effective, require a telescope-like mount, cannot be used handheld, and are generally specialty products. They also typically cost more than a good telescope, even when a mount/tripod is not accounted for.
For reference in resolving power, the disk of Jupiter or Saturn combined with its rings is about 40-50 arc seconds across. A small pair of binoculars can resolve these things somewhat but won’t show detail, e.g., the clear separation of Saturn’s rings or much in the way of Jupiter’s cloud bands. Likewise, you’re limited in your performance on stars, small deep-sky objects, and the Moon.
Essentially, a pair of 50mm or 60mm binoculars will rival a small 70-80mm telescope in light-gathering power, while telescopes of 90mm or greater aperture typically eclipse even the most powerful typical binoculars. As such, if you are buying a beginner telescope, it should probably be of 90mm or 100mm of aperture in order to provide deep-sky views better than a binocular; this is also usually the minimum for a good telescope with ample performance to show you much anyway. However, even a tiny 60mm refractor will beat the best binoculars for lunar and planetary viewing. There are other considerations to be made, too.
What Can You See?
The low magnification, limited resolution, and wide field of view of binoculars mean they are primarily meant for viewing large targets. Open star clusters, asterisms, the widest double stars, large emission nebulae like the Orion Nebula (M42) or the North America Nebula, and other such objects are ideal for binoculars. They can also show you at least a few dozen galaxies – though most will be faint smudges devoid of detail, the Andromeda Galaxy (M31) and Centaurus A show their dust lanes, while the Magellanic Clouds are fantastic under Southern Hemisphere skies. You can begin to see the Virgo Cluster of galaxies, or pairings/groups like M81 and M82, though they’re a lot smaller, dimmer, and harder to pick out than with a telescope – particularly with light-polluted skies. You can also detect globular clusters, though, with the exception of the gigantic and bright Omega Centauri, none can be resolved with even fairly powerful 70mm binoculars. Planetary nebulae are simply out of range of a pair of binoculars.
Solar System objects are rather lackluster in binoculars – the typical 7x to 15x magnification of most usable and affordable binoculars will show you similar details to Galileo’s telescopes. The Moon shows its biggest craters and other surface features, the phases of Venus can be resolved, and Jupiter shows its moons. With binoculars possessing 12x to 20x magnification, Jupiter’s cloud bands might be visible, and Saturn’s rings can be detected as “ears” much like Galileo saw (this may be possible at lower powers but is very difficult). You can also see Saturn’s moon Titan, and detect bright asteroids such as Ceres, Vesta, and Pallas, along with the ice giant planets Uranus and Neptune – Uranus and Vesta can be seen with the naked eye under dark skies if you know where to look, and binoculars may aid your attempts in doing so. All will look like star-like points, however.
Telescopes, of course, can reach high magnifications, gather more light than a pair of binoculars if they have sufficient aperture, and reveal detail on the planets and small deep-sky objects like planetary nebulae, galaxies, and globular clusters with 6” or greater aperture, as well as being able to split closer double stars and reveal fine detail in larger nebulae. You may not be able to scan as large a patch of sky with a telescope unless it is a small one designed for low-power views with very wide-field eyepieces, but unless the telescope is very small, there is almost always more you can eventually learn to see than with binoculars, though high levels of light pollution will obscure deep-sky objects with any optical instrument, no matter how powerful or large.
Quality
Except for the cheapest and lowest-quality binoculars with “ruby prisms”, “perma focus”, tiny aperture, and other such defects, most binoculars – even cheap or old ones – provide sharp views, and stability is only limited by the user or a third-party tripod. A pair of 7x50s from a flea market that you got for $10 or from your grandma’s basement will probably perform just as well as a new $30 pair like the Celestron Cometron 7x50s, and more expensive 7x50s have marginal gains in light-gathering and resolution, with the main improvements being in durability, comfort, and apparent field of view.
The same cannot be said with telescopes. Many telescopes under $300 USD have bad optics, bad tripods, low-quality accessories, or other such issues. A good 100mm Dobsonian telescope – the minimum we recommend – costs over $100 USD. A good small 60-80mm refractor might be available for less or found used for practically nothing, but it could cost at least $30 USD (the price of a decent pair of binoculars) just to get it working at all, given the low-quality eyepieces and accessories found with cheaper or older scopes. This often completely dooms any prospect of saving money compared to just buying a newer, and usually more capable, telescope of larger aperture already bundled with decent accessories. Binoculars are, of course, a one-stop shop, and again, they rarely come with eyepieces or other components that are straight-up unusable.
Ease of Use
A small and cheap telescope may be hard to aim or achieve low magnifications and a wide enough field of view to provide pleasing views of deep-sky objects or find them at all. Additionally, a tripod-mounted telescope takes a lot of time and effort to set up. A pair of binoculars is easy to figure out and scan the sky within seconds, as well as being portable enough to fit in even the smallest spaces without any need to worry about assembly/disassembly, weight, or bulk. This makes binoculars very conducive to the beginner astronomer learning to find their way around the night sky.