Processing math: 100%

SKY_FLAT_POL

Creates and files a flat field derived from eight frames using object masking to reduce artifacts

Description:

This recipe make a sky flat for UKIRT imaging from a series of eight sky or object frames combined using one of a selection of statistics. It is intended to be used to make a flat for polarimetry data. The data should comprise two spatial positions at the waveplate angles 0, 45, 22.5, and 67.5 degrees.

It performs a null debiassing, bad-pixel masking, and dark subtraction before combining the sky frames pixel by pixel to to make the flat. See the “Notes” for further details. The parameters of the flat are filed in the index of flats for future selection and use of the flat.

For best results the field observed should contain few stars and no bright ones.

Notes:

Output Data

Parameters:

USEVAR = LOGICAL
Whether or not to create and propagate variance arrays. [1]

Related Recipes

SKY_FLAT_FP, SKY_FLAT_MASKED, SKY_FLAT_POL_ANGLE.

Implementation Status: