Definition of F-Stop

A lens typically has two measurements of F-stop (aperture). The maximum aperture is when the lens is fully open and the minimum aperture is just before the lens is completely closed. The F-stop has a number of effects upon the final image, a low f-stop e.g. f/0.95 the lens will be able to pass more light in dark conditions and a maximum f-stop e.g. f/14 may be necessary where there is a very high level of light.

2D gels

Agarose gel


Camera lens focal lengths

CCD camera