sdss_calibv

pydl.photoop.photoobj.sdss_calibv()[source]

Return calibration for velocities from pix/frame to deg/day.

Returns:
Quantity

The conversion from pixels per frame to degrees per day

Notes

Assumes frame time difference of 71.72 seconds and pixel scale of 0.396 arcsec, both fixed. Also note that observations of the same part of sky from adjacent bands are separated by two frame numbers, so we multiply by a factor two.