16-Mar-2012
From Richard Schwartz:
There are two new control parameters that allow you to control the position
of the roll angle bins.
Set USE_REFERENCE_POSITION_ANGLE to enable this feature. It is a parameter for
the calibrated_eventlist class so it can be accessed from an image or visibility
class as well.
The specific value is set with REFERENCE_POSITION_ANGLE measured in radians from
solar north
For example, for an image object obj
obj->Set, /USE_REFERENCE_POSITION_ANGLE, REFERENCE_POSITION_ANGLE=-0.18
Here's a fun little demo to show it in action
.r hsi_image_script_4refposangletest
hsi_reference_position_angle_demo, obj,REFERENCE_POSITION_ANGLE=-0.18
The figure produced by the demo shows all 9 grid responses lined up on the
reference_position_angle.
The demo script, hsi_reference_position_angle_demo, is in the file
hsi_phz_stacker.pro.
If you examine that code you'll see that there is a stacked eventlist roll_angle
bin such that it matches the reference_position_angle exactly.