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DeepSkyStacker: The Essential Guide to Stacking for Astrophotography

: Taken with the lens cap on at the same temperature and exposure time as your lights. These subtract thermal noise and "hot pixels". deepskystacker

After stacking is complete, DSS opens a result window with tabs like "Light," "Luminance," and "Red/Blue." you need long exposures

When you photograph distant galaxies or nebulae, the light hitting your sensor is incredibly faint. To see detail, you need long exposures, but long exposures introduce significant and electronic interference. deepskystacker