A sliding or rotating cover which prevents light from entering the viewfinder eyepiece.
One of the problems with automatic exposure meters located inside the camera body is that stray light can enter the camera from the viewfinder as well as from the lens, throwing off the metering. Normally this isnt much of a problem, as you usually have your face pressed up against the back of the camera, blocking most light from entering. However it can be a problem if youre using the camera in some remote mode when you arent peering through the back.
This is where eyepiece shutters come in handy. Most high-end cameras have small retractable shutters or covers which block light from entering. Most mid to low end cameras do not have such covers, but many cameras ship with straps with plastic accessories that do much the same thing, albeit slightly less conveniently.
You can also try fitting a black plastic cap off a 35mm film canister - they fit many viewfinder frames.
Entry last updated 2004-02-11. Term 440 of 1487.
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