calculateImageParallacticAngle¶
- lsst.ip.diffim.calculateImageParallacticAngle(visitInfo, wcs)¶
Calculate the total sky rotation angle of an exposure.
- Parameters:
- visitInfo
lsst.afw.image.VisitInfo
Metadata for the exposure.
- wcs
lsst.afw.geom.SkyWcs
Coordinate system definition (wcs) for the exposure.
- visitInfo
- Returns:
lsst.geom.Angle
The rotation of the image axis, East from North. Equal to the parallactic angle plus any additional rotation of the coordinate system. A rotation angle of 0 degrees is defined with North along the +y axis and East along the +x axis. A rotation angle of 90 degrees is defined with North along the +x axis and East along the -y axis.