differentialRefraction¶
-
lsst.afw.coord.
differentialRefraction
(wavelength, wavelengthRef, elevation, observatory, weather=None)¶ Calculate the differential refraction between two wavelengths.
Parameters: - wavelength :
float
wavelength is in nm (valid for 230.2 < wavelength < 2058.6)
- wavelengthRef :
float
Reference wavelength, typically the effective wavelength of a filter.
- elevation :
lsst.geom.Angle
Elevation of the observation, as an Angle.
- observatory :
lsst.afw.coord.Observatory
Class containing the longitude, latitude, and altitude of the observatory.
- weather :
lsst.afw.coord.Weather
, optional Class containing the measured temperature, pressure, and humidity at the observatory during an observation If omitted, typical conditions for the observatory’s elevation will be calculated.
Returns: - differentialRefraction :
lsst.geom.Angle
The refraction at
wavelength
minus the refraction atwavelengthRef
.
- wavelength :