4. Image recorders

4.1 Coupling an optical instrument to a recorder

In all of the above, whether the observer is looking at the output image through the eyepiece or projected onto a screen, he or she is examining it in real time, with no memory other than his or her own. A time-delayed examination requires the recording of a single image or a temporal sequence of images using recording devices such as cameras, cinematographic cameras, camcorders or image acquisition systems.

Recorders contain a fixed or moving image receiver (photographic film, video tube, mosaic or photoelectric sensor strip) which must receive, in its plane, the real image to be recorded. From an eyepiece instrument for which the output image is at infinity, the real image can be obtained in two ways:...