Lens Converters and Lens Adapters

Converters are devices that sit between cameras and lenses. There are three types of converters: adapters, speed boosters, and teleconverters. With a lens adapter, lenses from different brands can be used together. Speed boosters can also adapt one lens mount to another, as well as reduce focal lengths and increase maximum apertures. The teleconverter does the opposite, increasing the focal length and decreasing the maximum aperture.