What is it?
Imaging is all about capturing light radiation so that it can be displayed for viewing in real time or via a storage
mechanism for viewing later. All imaging starts with an optical system ((mirrors and/ or lens) for focussing the light. The light is then directed into the eye for direct
viewing as in ‘simple’ binoculars or telescopes, or it is focussed onto a light capturing mechanism as in a camera (conventional photographic emulsion, or an electronic sensor - typically a CCD -
Charge Coupled Device)
Using sensors also enables a different window of light frequencies to be captured like infrared or ultraviolet which the eye
would not normally be able to see. Sensors can also ‘stare’ at the object for long periods of time and thus capture a great deal more light than the eye could
ever use. So a sensor can accumulate an image over seconds, minutes or hours to reveal images of very dim objects.
And, of course, once captured and stored, the image can be looked at lots of times - a technique used with photographic plates
when trying to determine the movement of a planet, comet, etc. against the backdrop of the stars. Once an image is captured electronically, it can be manipulated and
transported quite easily which makes it very powerful.
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