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n. A device on a camera that indicates, either optically or electronically, what will appear in the field of view of the lens.

n. A device on a camera that shows what will appear in the field of view of the lens; it helps the user target a subject, zoom and focus the image

n. optical device that helps a user to find the target of interest

"Looking through a glass viewfinder is such a treat, though — too bad it doesn't seem to actually line up very well with the actual pictures."

optical device   

pentaprism    collimator    glasses(russiangost    shallow-water    polycarbonate