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Observational Astronomy
Angles on the Sky
Pixel Size and Pitch
Focal Speeds/Ratios
Telescope Limits
Diffraction
Seeing
Focus
Guide
Magnitude
Types of Frames
Science Images
A science image or science frame is a light frame that has been calibrated to account for optical system and detector contributions or non-uniformities as well as to the top-of-atmosphere. For us, a science frame is a frame whose counts have been calibrated such that all of the counts present in the frame are thought to be proportional to the amount of spectral energy received from the source over the integration time if there were no atmosphere. It is from these frames that you can estimate most physical quantities.
Though they are often necessary, the generation of a science image for our purposes does not include astrometric calibration.
Measurements
Sources