Dark currentΒΆ

The dark current step removes dark current from a JWST exposure by subtracting dark current data stored in a dark reference file. The reference file records a high signal-to-noise ramp of the detector dark signal (i.e., the signal detected in the absence of photons from the sky). It is constructed by averaging the individual frames of many long, dark exposures.

This link to the JWST pipeline provides detailed information on this step.