I get asked this question fairly often and it is not surprising as the terms “auto focus binoculars” and “self focusing binoculars” are very misleading, but are often used by manufacturers of optics.

What you are probably describing are actually fixed focus binoculars, which have their focus set at the factory that don’t auto change and cannot be changed by the user. To achieve this they have a wide Depth of View and fairly low magnification, that usually allows you to focus on anything from about 30 feet to infinity.

This is not to say that fixed-focus binoculars are bad, they do have their advantages, time saved not having to focus can mean the difference between identifying that bird or not. Fixed focus is also often used on marine binoculars because they have far less moving parts than centre focus binoculars making them much easier to seal and make completely waterproof.

For more information you can read my full article on “Auto Focus Binoculars“