1 - Telescope
2 - Camera
3 - Film or CCD plane
L1 - Telescope objective
L2 - Eyepiece
L3 - Camera lens
Afocal photography, also called afocal imaging or afocal projection is a method of photography where the camera with its lens attached is mounted over the eyepiece of another image forming system such as an optical telescope or optical microscope, with the camera lens taking the place of the human eye.[1]