CCD Cameras info
What is a CCD imager?
On CCD cameras, a CCD ("charge-coupled device") is a detector sensitive to light. When light (consisting of discrete photons) hits the detector
surface of the CCD microchip, electrons are given off and stored in the detector elements,or pixels. A CCD microchip consists typically of thousands
of pixels. When CCD cameras are pointed at a brighter area of the sky, a larger number of photons come in contact with the chip. More photons generate
a larger number of electrons. Thus, a brighter portion of an image has a greater number of electrons stored in each pixel.
What is the basic role of CCD imaging in amateur astronomy? Why are amateur astronomers using these devices?
Using CCD cameras, the CCD imager attaches to the telescope's eyepiece-holder
in a roughly similar manner as a 35mm camera body is attached. The imager allows a very fast "picture" (digital exposure) to be taken of even faint
celestial objects. This exposure can be seen immediately on the display screen of a common personal computer and, if desired, can be stored on a disc for
future reference or printed out to obtain a hard copy of the image. These points will be expanded upon in the discussion that follows.
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