97459b3f___Description
[Type] domeflat [Description] 
Flats used to calibrate the pixel-to-pixel variations in the CCD. Blue side: At high dispersion (600 or 1200 grism), one should observe the twilight sky without a slit. This is the only means of getting enough blue counts in a spectrum that does not have sharp features. At lower dispersion (300 grism), one can acquire a dome flat. Red Side: One obtains 'standard' dome flats. Note: The code currently attempts to distinguish between domeflats and twilight flats by considering the time the exposures were taken and the position of the dome slit relative to the pointing. There is no header keyword that specifies the dome lamps being on or off. Therefore, pay extra attention to these files to make sure they are labelled correctly.
Description