Guide to buying the best binoculars for observing the night sky
One of the easiest and most enjoyable ways to travel in space without leaving Earth is to buy binoculars and observe the cosmos from an armchair on a night under clear and dark skies. . But for the best experience, it's a good idea to choose binoculars that are designed for astronomical work and sky observation. You should know that we have collected sky observations. If you're looking to make more use of this optical tool, you can review 8 key points for buying binoculars, and then when you're ready to buy a pair of binoculars, take a look at our selection of the most useful binoculars.
buy binoculars
seeing with the brain
The human eye is amazingly adapted to perceive light and color and react to light and dark, but it is the brain that It creates your moving, 3D image of the world, and the difference in data between your left and right eyes is processed by the mind as depth information.
Even though the vast distances in the cosmos challenge depth perception , with prior knowledge of observational goals, you can see the world in three dimensions to some extent, and binoculars make this mental exercise faster and easier.
Binoculars are an extension of the eyeball that by keeping the eyes away from distracting information, focus all the visual circuits of the brain on enjoying the wonders of space.
Closed. Binocularly, you can see 25 or even 50 times more stars than with the unaided eye, and this is not only due to magnification, but also due to the phenomenon of "perceptual narrowing" (perceptual narrowing) and focusing the focus on the sky.
Binoculars vs Telescopes
Telescopes are large and must be mounted on tripods or boxes for stability. to be specially placed When using a telescope, you have to adjust the objective lens with an outstretched arm, but binoculars can be firmly placed in the eyeball for even more stability. This is where binoculars have an edge over even the best telescopes out there.
Telescopes make objects appear larger, but their main job is to collect light. At higher magnification, an object appears fainter. This is especially problematic when observing deep-sky targets such as comets, galaxies, and open star clusters.
Most telescopes use a single eyepiece, but binoculars really give you "two eyes" and give you twice the chance. To get your brain used to starlight. Remember, seeing happens in your mind, and for the most enjoyable experience, you need to focus your attention on the target.
Telescopes only show a small area of the sky, but binoculars, with a wider field of view, can scan Skyscopes help find a variety of targets and provide a better understanding of how cosmic objects relate to each other, including constellations.
Many telescopes show the sky inverted or mirrored, but binoculars view the world from It displays a real view. Telescopes are also expensive due to the construction technology and the amount of materials used, but binoculars can be had at reasonable prices.
The Right Binocular
Now think about when What to look for when choosing the best night sky binoculars Here are a few key points.
Checking the Specs
Understanding a few numbers will help you better decide which binoculars are best for your specific purposes. These numbers are listed below in order of importance.
Field of View
In binocular specifications, there are one or two ways to know the field of view. The spec might say something like this: 298 feet (90 meters) at 1,000 yards or 5.7 degrees; These numbers are equal. If you are only given the width of the field in degrees, you can easily calculate 52 feet per 1 degree.
For comparison, your clenched fist while holding your arm outstretched. , it covers about 10 degrees of the night sky, or the width of the moon's disk is about 0.5 degrees. are separated For example, 12x70 or 25x100, etc. The first number is the amount of binocular power. In other words, what is the magnification of this binocular? The second number indicates the diameter of the large lens in front of the observatory in millimeters.>
The size of a binocular is also something that should be taken into consideration. For example, by dividing the size of the object by the power of the telescope, the diameter of each of those small circles from which you look is obtained.
This Bright spots (disc-shaped) are called exit pupils and are considered a kind of virtual aperture. Higher powered binoculars produce smaller exit pupils. For example, 60x12 binoculars produce a 5mm exit pupil, or 8x60 binoculars give you a 7.5mm exit pupil.
The exit pupil should almost match the pupil of the eye and it is normal that human eyes change with age. For example, a middle-aged person whose eyes have adapted to the dark will open to a pupil diameter of about 5 mm, but the pupil of a 12-year-old child can reach an opening of approximately 8 mm.
Binoculars with low power, which are usually smaller, Often produce a larger exit pupil diameter. So keep this in mind, especially if you're buying binoculars as an adult.
Also, when buying expensive binoculars, check the shape of the exit pupils, which appear as floats in the eyepieces, to make sure they are perfectly round. With access to the dark sky, you can also check the change in apparent brightness with increased magnification.
If you can hold real binoculars directly in front of you, poor optics can clearly destroy the edges of the image. When shopping online, you can pay attention to the brand and background of the seller and read reviews of a product. For example, the optics of "Celestron", "National Geographic" and "Olympus" brands have passed their test well over the years.
Less power but more practical
There are different configurations in the market and one size definitely does not fit all. Some astronomers prefer higher magnifications to spot thousands of points of light within dense star clusters or fine structures in galaxies. Others opt for the "spacewalk" experience with a wide and omnidirectional field of view, preferring light weight and portability to the power of binoculars. Some people like big cameras that can only be used with a tripod.
But in general, the best binoculars are the ones you can always have with you. So buy a product that you're likely to use the most, whether it's in the yard or on a trip or anywhere else. If these are your only binoculars, it is recommended that the objective lens be no larger than 50mm (the number after the x like 7x40) and that the magnification is no greater than 10x.
Note that even these smaller binoculars can be very useful as long as they use high quality lenses. For example, with 8x35 binoculars, you can watch birds during the day and watch the stars dance at night without hurting your arms. By the way, a wider field of view is usually considered an advantage for watching the sky.
For example, when observing a meteor shower, you never know exactly where the next meteors will appear, and with a wider field of view, you will see more meteors. Therefore, before choosing the largest observation tools, be sure to think carefully about the dimensions and weight of the binoculars and the targets you will observe with them. Wet areas are inevitable during observational activities, so depending on the time, place and manner of using the binoculars, waterproofing becomes important. Many modern binoculars have a rubber coating to protect against water and shock.
But binoculars Cheaper ones may have internal water problems even when supplied from the factory. Air filled with water vapor trapped inside the instrument can cause fogging, image errors or rusting of your binoculars. So look for items that have been degassed with nitrogen before insulating the optics.
Tripod connection
Sometimes the stability of the binoculars can help a lot, and therefore the ability to place them on have a base To do this, make sure your binoculars have a support to attach the base to.
The problem with regular tripods It is that most of them are not able to bend properly to cover the whole sky, but there are special arms for binoculars that can overcome this shortcoming.
Importance of Porro prisms
In the market Today, the fastest way to identify binoculars that could be useful for space exploration is to verify their prism design. Around 1850, Ignazio Porro, an optician from Italy, discovered that a triangular glass block with a 90-degree corner deflects the light path twice and causes the final image to appear at the same angle to reality. p>
When two regular geometric Porro prisms are glued together at right angles, they "correct" the image in a compressed space. With this setting, objects appear correctly in the image and "what you see is what you see."
Porro prisms are almost always placed outside the eyepiece. That is, they are wider than the lenses you put your eyes on. This prism gives the binoculars a classic curved look and makes them naturally fit in the hand.
Binoculars are more compact but often use "roof prisms" which are lighter and can be It made them much cheaper than Porro prisms.
Using night sky binoculars on the ground
If, in addition to observing the night sky, you plan to buy binoculars for watching games, Whether you use it for concerts, bird watching, boating, or any other terrestrial activity, there are two important things: close focus and light weight.
Close focus
As binoculars become more specialized for astronomy, they usually They will also have a deeper focal point because they are designed to look at objects that are billions of kilometers away, essentially at infinity. But birds and animals and other things on earth are much closer. So to deal with this dual use, make sure your new binoculars can focus fairly close as well.
Light weight
Before buying, make sure that the binoculars are not too heavy to hold, because depending on the speed of the target, you may need to hold it for hours.
The center of mass should be in the prisms and should be placed easily above the palm. Objective lenses that are too large in front cause pressure on the wrist by creating leverage. Muscle fatigue also causes image distortion, and this increases the importance of choosing a lighter binocular.
Some suitable binoculars for astronomical activity
Celestron 20x50 upclose G2 binoculars
One cannot talk about astronomical observation tools and ignore the Celestron brand. This brand includes a wide range of binoculars from affordable models to expensive flagships.
The company's 20x50 camera is actually a great binocular for watching terrestrial phenomena from concerts to birds, but it is also a desirable option. To begin exploring the night sky.
This camera uses BaK-7 glass for its Porro prism, which is multi-coated to improve light transmission, resulting in brighter and sharper images with It provides you with high contrast and 20x magnification.
Sturdy aluminum body and water resistance make it a great option for years of use. Another positive point of this binocular is its ergonomic body, which with a rubber coating and indentations suitable for fingers, helps to work easily and not slip in the hand.
This camera also has a special groove for connecting to a tripod. It is considered that it will be very useful for longer observation of a target.
View product in SafirSoft
Nautic 7x binoculars 50
This Bresser brand binocular also uses Porro prism and due to the quality of the glasses, you can see Provides clear information to the user. Nautic camera, as its name suggests, is specially designed for marine applications and wet environments.
For this reason, it has a durable and completely waterproof body that allows use in any harsh conditions. . In addition, the presence of a compass with internal light will help in orientation. It was used to start observing the night sky and identify the constellations more accurately. .jpg">
If you are looking for a pair of binoculars with a good price and a good use for the night sky, and at the same time spending money for more well-known brands is not your priority, this binoculars will be a good option. .
Using Porro prism, magnification between 7-15x, 50mm objective lens and 22mm eyepiece provides a clear view in front of your eyes. Being waterproof and a strong metal body makes it possible to use these binoculars in different conditions and at the same time its beauty is preserved.
Nikon is also a well-known brand in the world of optics, and this also applies to its observation tools. The attractive body in the style of cameras of this brand is the first thing that attracts attention when facing this binocular.
50 mm aperture diameter, suitable weight and field of view of 374 feet at 1000 yards are among the features of this binocular. . In this way, with high optical quality and suitable aperture diameter, It will be a permanent and suitable tool to start observing the wonders of the night sky.
View the product in SafirSoftSkyMaster 15X70 Celestron Binocular Camera
Finally, the Celestron Skymaster series camera can be an ideal option for observing the night sky at a reasonable cost. This binocular weighs more than 1 kg and is somewhat heavy, but it is still possible to hold it in your hand for a short time. With an objective diameter of 70 mm, this binocular has a magnification of 15 times, which is very desirable for continuous and recreational observation of the night sky. Using BaK-4 glass for the prism, it provides a clear view even in low light conditions. It is considered an excellent option for a full night of observation, from dusk to dawn. A subject that is waterproof and has a rubber body to absorb impact is also more practical. Even if you look at it with the naked eye, it is really an amazing place. All you have to do is look for a clear, dark night sky and then look up and enjoy. The pleasure that with a binocular even in the sky of big cities can deepen and surprise you.
Photos: binoculars and its structure
Credit: Space/Jeremy Lips & Dave Brody