Kowa Genesis Prominar 8×33 on test: Very good binoculars

Eye cups
Plastic shells, which can usually be opened in two to three steps, through which you look into the telescope. They protect the eye from light from the side and help you focus the view through the telescope. People who wear glasses leave the eye cups open because the glasses give them more distance from the eyeball.

Construction method: roof edge or Porro
These two terms describe the common types of all telescopes. “Porros” are wide, old-fashioned binoculars that you can find, for example. B. knows from the Bundeswehr. Roof prism binoculars are slimmer and more compact, but sometimes again – this design is established. The deciding factor here is the arrangement of the lenses: Porro glasses are schematically simple, but the construction of the prisms requires more space in width. Roof prism binoculars are more complex and difficult to create – however, as engineering progressed, they became better and better and today represent the lion’s share and flagship of the quality of modern binoculars.

Diopter compensation
This is the mechanism – usually on the right lens, sometimes connected to the central motor – by which the differences in vision between the two eyes are compensated.

Ball armoring
The smoothest layer on the outer shell of the telescope. On the one hand, rubber arms provide a useful grip (even with wet hands), and on the other hand, it protects the binoculars from impact. The manufacturer Zeiss, for example, uses nitrile butadiene rubber.

middle shot
A central adjustment wheel between the two lens tubes. Here the picture is aimed with only one finger.

The diameter of the lens
The second number in the name of many binoculars – in this test is “32” or “30” and “42”. It indicates the diameter of the opening farthest from the eye in the telescope. The following applies: the larger the diameter of the lens, the more light enters the binoculars. Compact glasses are usually 32 or 40mm, binoculars with 50mm or more are intended for evening activities, eg B. when hunting.

Depth of field
This refers to the area where the user sees what is seen through the optics as sharp. If the telescope has a deep depth of field, the area perceived as sharp is wider than with a telescope with a shallow depth of field. Because then you have to refocus frequently, long viewing can get a bit tiring.

field of view
The field of view of binoculars is usually given in meters. The number describes the size of the part of the image visible at a distance of 1,000 meters. In general, the bigger the field of view, the better.

expansion
The first number in the name of many binoculars – in this test is “8” or “12”. This means that looking through a mirror makes things appear eight or twelve times larger than they are with the naked eye.

compensation
In general, you want to minimize light reflection on the lens – less light should be reflected and more should penetrate the lens. While a simple telescope only receives about 50% of the light, a fully covered mirror reaches values ​​of 75%. Thanks to the so-called full coating, the top glasses have a transmittance (light transmission) of more than 90%. This coating is achieved through the complex vapor deposition of various, very thin layers on the glass.