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Optical Telescopes and Cameras
•Properly curved lenses and mirrors can form “Images”
–All the light leaving one point on object gets “reassembled” at one point on the image.
•In a camera you put film or an electronic sensor at the image to record it.
•In a telescope you put a magnifying glass (an eyepiece) near the image to see a magnified version of it.
•Most astronomers don’t spend much time looking through telescopes
– they put recording devices at the image and use them as large cameras.
From our text:  Horizons, by Seeds