10×42 vs 10×50 binoculars – Which is the right option for you?

10×42 vs 10×50 binoculars are two of the most popular types that almost the main lines of famous brands manufacture. Reading this article, you will have an overall comparison between these two binoculars. 

What are 10×42 and 10×50 binoculars?

According to the first number, which represents magnification, huge things appear to be when viewed with binoculars. The size of the lens or the objective lens’s diameter is indicated by the second number. As a result, the 10×42 binocular has a 42-millimeter lens and a 10x magnification. A 10×50 binocular displays 10x magnification with an objective lens that is 50 millimeters in diameter.

Some typical binoculars in 10×42 and 10×50 on the market now are Celestron UpClose G2 10×50 binoculars, Leupold BX-4 Pro Guide HD 10x42mm, Bushnell PowerView 10×50 Wide Angle Binocular. 

10x42 and 10x50 binoculars
Comparison between 10×42 and 10×50 binoculars

Comparison of 10×42 vs 10×50 binoculars

I will first present a broad comparison of these two varieties of binoculars before delving further into each feature. Finally, I compare how well 10×42 and 10×50 binoculars serve general purposes.

10×42 binoculars 10×50 binoculars
Size and weight More lightweight and more compact A bit larger and heavier
Viewing distance Both have fairly good viewing distance
Image stability Both have an average image stability
Field of view Both has FOV of around 6 degrees
Image brightness & Low light performance Less notable light-gathering ability Better at image brightness and low light performance
Exit pupil EP = 4.2mm EP = 5mm

Size and Weight

Due to the objective lens’s 8-millimeter wider diameter, 10×50 optics are unquestionably larger than 10×42 ones when comparing dimensions. Additionally, 10×50 binoculars are typically a little longer than their 42mm equivalents. The distinction here, though, is quite small (usually under 10mm).

A 10×50 binocular is slightly heavier than a 10×42 model using the same level of materials because more glass is needed to manufacture the lenses and more material is needed for the slightly bigger body. Glass is a rather heavy substance.

If maintaining a lightweight is important to you, you can make significant weight savings by choosing a binocular with a polycarbonate chassis and plastic focus wheel instead of a metal one.

Viewing distance

The magnification of a pair of binoculars determines the viewing distance. Both 10×42 and 10×50 binoculars have a 10x magnification, which means that when you look at something through them, it seems 10 times larger than it would if you were simply using your eyes. The magnification number does not directly relate to the viewing distance, however, the farther the view distance, the higher the magnification number.

Binoculars with a magnification of 10×42 and 10×50 have the same viewing distance. 10x is an average magnification, so both binoculars show a fairly good viewing distance. 

Image stability

Magnification has an impact on a binocular’s capacity to maintain an image. The stability of the image decreases with increasing magnification. To see details, you must keep the optics steady. As the magnification goes up, the view seems to move more. It could be difficult to hold your binoculars steadily, especially if you’re worn out after a long day in the field. Both 10×42 and 10×50 binoculars have the same image stability. 

A 10x binoculars are not heavy but not as lightweight as an 8x. Therefore, I frequently choose 8x or 10x binoculars for simple hobbies like birdwatching, sightseeing, or hunting. I decide on 12x since astronomy necessitates a great viewing distance. With too heavy binoculars to hold steady, I suggest using a tripod. 

Field of view (FOV)

Real field of view is defined as the angle of the visible field, as viewed through the binoculars while not moving them, as measured from the center of the objective lens. The view field is more expansive the larger the value. For instance, binoculars with a larger field of view are useful for tracking swiftly moving wild birds.

This holds true for discovering tiny nebulas or star clusters during astronomical studies.

When using binoculars, the apparent field of view is the angle of the enlarged field. The traditional approach previously utilized involved multiplying the real field of view by the binocular magnification to determine the apparent field of view. For 10x binoculars, FOV is around 6 degrees

Image brightness and low light performance

The larger surface area of 50mm lenses means that they have the potential to capture more light than 42mm ones. 

A good quality 10×42 binocular can capture and transmit enough light to your eyes during the day in normal lighting conditions for you to perceive a bright, high-quality image; therefore, in these circumstances, it’s highly unlikely that you’ll be able to tell the difference in brightness between the views of an equal quality 10×42 and 10×50 binocular.

The extra capabilities of the larger instrument, however, come to the fore and you start to see the difference in the image when the light level is not perfect, such as immediately before sunrise, at dusk, or even in a heavily forested area.

Source: Ebay

Exit pupil

When you hold a pair of binoculars and focus the objective lenses at a bright light, the bright circle in the middle of each eyepiece is the exit pupil. When using binoculars in low light or for astronomical observation, the brightness of the view field, which increases with increasing diameter, is a crucial factor to take into account.

Exit pupil = The effective diameter of the objective lens ÷ Magnification. According to the formula, 10×42 binoculars have an EP of 4.2 mm while 10×50 ones represent a 5mm EP. 

The diameter of a human eye pupil varies from approximately 2 mm in strong light to a maximum of roughly 7 mm in complete darkness. The exit pupil in a pair of binoculars needs to be at least the size of the pupil in our own eye in order for an optics-aided eyeball to utilize the available light in any given condition. Your eye will become “light starved” if it is smaller (not enough light reaches your eye). Typically, this takes place around dawn and dusk.

Source: Nikon

Applications of 10×42 vs 10×50 binoculars


We frequently observe the stars in low light, thus a binocular with a large lens and good low-light performance is ideal. Therefore, because 10×50 binoculars have a great light-gathering capacity and produce good-quality images, I advise using them for observing the stars. 

However, for stargazing purposes, high magnification such as 12x or 15x binoculars are still better. With these binoculars, you had better use a tripod so that the binoculars can be stabilized during stargazing time.

Additionally, the binoculars you select will depend on where you plan to see the stars. If you want to see stars in an urban region where the sky is quite bright due to light pollution, I recommend using a high magnification because you will be staring at pinpoints of light, which will be naturally bright. The dark sky will appear grey from too much light collection, weakening the contrast between the subject and the background. However, a wider exit pupil is advised in areas with a gloomy sky, like the countryside.

Hunting and birdwatching

8x and 10x binoculars are used for hunting and birding since they are light, portable, and provide less vibrating pictures.

In daylight, I suggest 10×42 binoculars because they have a smaller lens, are lighter, and are better suited for activities that require a lot of walking and moving around.

However, if you go night hunting and need an excellent light-gathering binocular, you might want to think about going for a 10×50 because you can get a brighter image to help you find the animals.

birdwatching for beginners


People frequently travel in good weather with adequate lighting for sightseeing, eliminating the need for binoculars with excessively good light-gathering capabilities. Instead, those who go sightseeing require handy binoculars that are portable and tiny.

Thus, 10×42 binoculars can serve you better with sightseeing activities if you find 10×50 ones are too heavy to carry around on a long day. 

Concerts/ Theaters

The darkness of nighttime shows and concerts calls for binoculars with a bigger exit pupil that provides a brilliant view. High optical performance 10×50 binoculars let you perceive even subtle facial emotions.

However, for concert halls and theaters, lightweight binoculars with a magnification of 4x to 8x are preferred. It’s handy to have compact, lightweight binoculars that can be easily stored in bags or pockets. With lightweight binoculars, you can minimize the strain on your arms when using them for extended periods.


In conclusion, 10×42 vs 10×50 binoculars have the same magnification but a different objective lens diameter. Each of them is therefore appropriate for a particular purpose. To find the best pair of binoculars, take into account your needs, such as light brightness, weight, or image stability.