Image Details
Caption: Figure 6.
Astrometric precision of the DECaLS CCDs, computed by comparing the derived positions (using the WCS) of bright stars with their positions in the Gaia DR1 catalog. The N4 CCD is one of two central CCDs in the DECam mosaic; the other eight CCDs shown are edge CCDs in the mosaic and represent regions with the largest astrometric and PSF distortions.
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