Leaf shutter
From Wikipedia, the free encyclopedia
In photography, a leaf shutter is a type of camera shutter consisting of a pivoting metal leaf and spring which briefly uncovers the camera aperture to make the exposure.
Simple leaf shutters typically have only one shutter speed and are commonly found in disposable cameras and cheap point-and-shoot cameras. In its more complex forms it can have variable shutter speeds.
The main advantages of the leaf shutter are:
- Relatively simple construction is possible.
- No cocking mechanism
- No variable shutter speeds
- Less costly than a focal plane shutter
- Flash synchronization possible at all speeds.
- Small size is achieved by placing the shutter at the focal convergent point either inside the lens or inside the camera body.
- Many versions have no connection between the release mechanism and the film advance, making multiple exposures possible.
Some of the disadvantages of the leaf shutter are:
- Shutter speeds are limited to 1/500th or 1/250th of a second.
- Although also listed as an advantage, accidental multiple exposures are common problem.
- Imprecise speeds (e.g. Holga camera)
[edit] Diaphragm shutter
A diaphragm shutter is a type of leaf shutter consisting of a number of blades which briefly uncover the camera aperture to make the exposure. Leaf shutters use thin blades that move across the shutter aperture to cover and uncover it[1]. While the vast majority of leaf shutters are diaphragm shutters, there are some simpler versions in which one or two blades simply uncover the aperture without forming the characteristic iris of the diaphragm shutter. The blades, which may be either metal or some other material (like fiber), are generally curved to help form a close approximation to a circle on opening. Diaphragm shutters typically have at least 3 blades, and almost always an odd number of blades, up to 5 or more.
The term diaphragm shutter has also been used to describe an optical stop with a slit, near the focal plane of a moving-film high-speed camera[2].
