8×20 VS 10×25 Binoculars | Optics Trade Debates

By Maruša Justinek Oct 13, 2020

Hello and welcome to another episode of Optics Trade debates. Today, we are going to compare two categories of pocket binoculars: 8×20 and 10×25. It is a common question we get, and it is probably the most difficult one to answer, as the differences are so small.

Let us begin with some general features. All of these binoculars belong to the category of pocket binoculars. They are mostly 8×20 and 10×25 binoculars, even though there are some variations, like 8×22, 10×26, and 10×24. They are all extremely small, and always weigh below 300 g. The binoculars usually come in a dual-hinge design, which means you are able to fold them two times. The reason for this is so you can put them in your pockets, hence the name.

The housing is usually covered in plastic, except for some higher-priced models, which are covered in aluminum or magnesium. The binoculars come with a roof prism Schmidt-Pechan system. Porro prisms with this configuration are extremely rare, but they do exist. It is however true that with a Porro prism design, they are not as small anymore and already fall into the category of compact binoculars.

They start really cheap, at 50 €, and the best binoculars in this class go up to 800 €-900 €, which is a bit narrower of a price range compared to other categories. The eye-pieces are both of a rubber type and plastic. The rubber eye-pieces can fold, and there are also twist-up eye-pieces (in most cases only 2 positions). The focusing is always in the center, there are rare models where there is individual focusing for each eye.

It is true, however, that there are many systems of diopter compensation with this type of binoculars. Some have it on the eye-pieces, and others on different positions – either on the inside of the bridge or around the tube. You can find many different technical solutions for diopter compensation with this type of binoculars. They do have short eye relief, so those wearing glasses will not be satisfied when using them. They are perfect for presents for children and because of the narrow eye-pieces, they will fit their small eyes.

Moving on to suitability. These binoculars – because of their size – can be stored in every pocket and because of that, they are more suitable for leisure activities like cycling, walking, or to a safari. You can even take them to the mountains, even though the compact category is more popular, as the viewing experience is better. Pocket binoculars do not offer the most comfort when viewing, because the eyepieces are quite narrow. You often have to hold them slightly away from your eyes, as if you press them onto your eyes, you will experience some discomfort.

Regarding the build features, the 10×25 binoculars are a bit taller than the 8x magnification ones. When it comes to weight, there is about 20 g-30 g of difference, which is not much – hardly noticeable. Except for the length, everything is similar and when you put them together, they are almost equal in size. Price-wise, there is a 5%-10% difference and, usually, the 10×25 models are more expensive.

Regarding the field of view, pocket binoculars usually do not have a wide field of view. With the 8x magnification, you get around 110 m of the field of view, and with 10x magnification, you get 90 m of the field of view. Neither performs well in low-light, these are purely day-time binoculars, even though 8x is better for viewing at dusk or dawn.

In terms of comfort, 8x magnification is a bit more comfortable – it has a little bit bigger exit pupil and 1 mm more of eye relief. This is it when it comes to differences, everything else is more or less the same, so it is difficult when deciding between the two. If you pick higher magnification, you will be to observe details more clearly, even though you get a narrower field of view. But you want a wider field of view, go with the lower magnification. If you are a novice user, go with the 8x magnification also.

This is it. We have some individual reviews on various pocket binoculars. If you have any additional questions, use the comments below, and see you in our next video. Goodbye.