F-stop is a consistent way to measure lens aperture, and helps photographers control exposure and depth of field. It is noted with an f followed by a slash and number, for example f/2.8.

The maximum aperture is noted in the lens – for instance, a Nikon AF-S 85mm f/1.8G sports a maximum aperture of f/1.8, while a Canon EF 16-35mm f/4L IS USM features a maximum aperture of f/4.

An aperture ring allows you to set the f-stop directly from the lens as opposed to a camera control dial. Example: Fujinon XF 8mm F3.5 R WR OIS is short for optical image stabilization.

The aperture - also described as the f-number or f-stop - is the size of the lens opening through which light passes. Lenses that have a large maximum aperture such as f/1.8, ...

One notable feature of the Night Walker series is its maximum T-stop of 1.2. This fast aperture offers filmmakers the ability to isolate subjects across a variety of situations.

An aperture ring allows you to set the f-stop directly from the lens as opposed to a camera control dial. Example: Fujinon XF 8mm F3.5 R WR OIS is short for optical image stabilization.