azel_model

pytelpoint.transform.azel_model(coo, ia=0.0, ie=0.0, an=0.0, aw=0.0, ca=0.0, npae=0.0, tf=0.0, tx=0.0, **kwargs)

Apply 8-term alt-az pointing model to set of raw alt-az coordinates and return corrected coordinates. Parameter names match those used by TPOINT(tm): IA, IE, AN, AW, CA, NPAE, TF, and TX. See TPOINT(tm) documentation for more details.

Parameters:

cooSkyCoord instance

Raw Az-El coordinates to correct via pointing model model. Must be in an AltAz frame.

iafloat (default: 0)

Azimuth index value (i.e. zeropoint)

iefloat (default: 0)

Elevation index value

anfloat (default: 0)

North-South misalignment of azimuth axis

awfloat (default: 0)

East-West misalignment of azimuth axis

cafloat (default: 0)

Left-Right collimation error. In an alt-az mount, this collimation error is the non-perpendicularity between the nominated pointing direction and the elevation axis. It produces a left-right shift on the sky that is constant for all elevations.

npaefloat (default: 0)

Az/El non-perpendicularity. In an alt-az mount, if the azimuth and elevation axes are not exactly at right angles, horizontal shifts occur that are proportional to sin(el).

tffloat (default: 0)

Tube flexure term proportional to cos(el).

txfloat (default: 0)

Tube flexure term proportional to cot(el).

Returns:

new_cooSkyCoord instance

New coordinates with azel pointing model applied.