Shutters
Click to explore the different types of shutters used in digital cameras.
Click to explore the shutter speed's effect on exposure.
Click to explore the shutter speed's effect on motion.
A leaf shutter.
There are three different kinds of shutters used in digital cameras—leaf, electronic, and focal plane. Leaf and focal plane shutters are both mechanical and have moving parts—leaves or curtains.
- Leaf shutters, alone or combined with an electronic shutter are used on some point and shoot cameras. On some inexpensive cameras, the shutter also acts as the aperture by varying how far it opens.
- Electronic shutters simply turn the sensor on and off to capture the exposure. It's like turning a vacuum cleaner on to start accumulating dust and off to stop. These shutters are found in the cheapest cameras, but ironically also in the most expensive. When precision designed they can be exceptionally accurate.
- Focal plane shutters, found in all digital SLRs open one curtain to begin an exposure and close another curtain to end it (above, top). At high shutter speeds, there is a slit between the two curtains moving across the image sensor (above, bottom). On newer cameras the curtains run vertically. This makes them faster than older shutters that ran horizontally because they have less distance to cross. This faster speed makes it possible to have a faster flash sync shutter speed.
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