Sky2Pix_ConicPerspective

class astropy.modeling.projections.Sky2Pix_ConicPerspective(*args, **kwargs)

Bases: Sky2PixProjection, Conic

Colles’ conic perspective projection - sky to pixel.

Corresponds to the COP projection in FITS WCS.

See Conic for a description of the entire equation.

The projection formulae are:

\[\begin{split}C &= \sin \theta_a \\ R_\theta &= \frac{180^\circ}{\pi} \cos \eta [ \cot \theta_a - \tan(\theta - \theta_a)] \\ Y_0 &= \frac{180^\circ}{\pi} \cos \eta \cot \theta_a\end{split}\]

Parameters:

sigmafloat

\((\theta_1 + \theta_2) / 2\), where \(\theta_1\) and \(\theta_2\) are the latitudes of the standard parallels, in degrees. Default is 90.

deltafloat

\((\theta_1 - \theta_2) / 2\), where \(\theta_1\) and \(\theta_2\) are the latitudes of the standard parallels, in degrees. Default is 0.