ACS-SBC-DITHER-BOX
pointing patterns
This is a two-dimensional 4-point dither pattern, with the following allowable parameter ranges:
Pattern_Number: 1
Pattern_Type: ACS-SBC-DITHER-BOX
Pattern_Purpose: DITHER
Number_Of_Points: 4
Point_Spacing: 0.01 - 10.0 (arcseconds)
Line_Spacing: 0.01 - 10.0 (arcseconds)
Coordinate_Frame: POS-TARG
Pattern_Orient: 0.0 - 360.0 (degrees)
Angle_Between_Sides: 0.0 - 360.0 (degrees)
Center_Pattern: ? (YES or NO)
The following versions of this Pattern_Type are projected
onto the detector pixel space in the graphic above.
The default pattern has relative pixel coordinates
(0, 0), (5.0, 1.5), (2.5, 4.5), (-2.5, 3.0).
It is a parallelogram pattern designed for half-pixel sampling in both x and y, with overall dimensions large enough to help reject the larger detector artifacts.
Pattern_Number: 36
Pattern_Type: ACS-SBC-DITHER-BOX
Pattern_Purpose: DITHER
Number_Of_Points: 4
Point_Spacing: 0.179
Line_Spacing: 0.117
Coordinate_Frame: POS-TARG
Pattern_Orient: 20.11
Angle_Between_Sides: 64.33
Center_Pattern: NO
POS TARG equivalent: 0.000, 0.000
0.168, 0.062
0.084, 0.143
-0.084, 0.082