Glossary

By Neil Rosenfeld

Below are some terms that are used to describe photo equipment. If there are some terms you think we should have included, email us at photo@ebay.com with the term and the definition.

Focal-plane shutter: A built-in camera mechanism containing a metal or fabric curtain for exposing film. It sits in front of the focal plane (just in front of the film).

Ground glass: A piece of glass which is roughened on one side to allow an image to be focused on the other side. The viewing screen in reflex and view cameras are ground glass.

Leaf shutter: Also known as a diaphragm shutter. A camera mechanism containing a circle of overlapping metal leaves for exposing film.

Macro lens: A lens designed for close-up photography. Sometimes known as a micro lens.

Rangefinder: A camera which has a lens for exposing the film and a viewfinder for composition and focus. Unlike reflex cameras, there is no mirror or viewing screen.

Reflex camera: A camera containing a built-in mirror that reflects the scene onto a viewing screen. See single-lens reflex and twin-lens reflex.

Single-lens reflex (SLR): A camera which has a hinged mirror that reflects the scene for composition and focusing. The mirror swings out of the way to expose the film. There are both 35mm and medium format SLRs.

Twin-lens reflex (TLR): A camera which has one lens for viewing and another for exposing the film.

View camera: Originally intended for outdoor "views" these cameras are also called large format cameras, and they come in both field and studio models. The image is focused on a "ground glass" that is separated from the lens by a flexible bellows. These cameras allow movements of the lens plane and, on some models, the film plane as well, to adjust perspective and focus. These cameras are designed for use with sheet film but there are adapters available that allow the use of roll film.

Have comments or suggestions about our Photo area? Click here to give us your opinion.

The preceding material was written by Neil Rosenfeld. These are the opinions of the author, not the opinions of eBay, and therefore eBay does not validate the accuracy of or endorse these opinions.