TUNE_SKYPOLY

Type: _INTEGER
When TUNE_SKYPOLY>0 it specifies the degree of polynomial to use when trying to fit to the sky intensity at any single constant-X / lambda increment. These polynomials are used to predict the contributory sky intensity in the object pixels.

The default value is TUNE_SKYPOLY=0 to obtain sky averaging (i.e., sky model is constant at each order/column).

Set TUNE_SKYPOLY=-1 when there is no sky to be modelled (i.e., sky model is zero everywhere).

Initial suggested value: 0.