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ACS pointing patterns

ACS-SBC-DITHER-LINE
pointing patterns

This is a one-dimensional dither pattern, with the following allowable parameter ranges:

     Pattern_Number: 1 
       Pattern_Type: ACS-SBC-DITHER-LINE
    Pattern_Purpose: DITHER
   Number_Of_Points: 2-9
      Point_Spacing: 0.01 - 10.0  (arcseconds)
       Line_Spacing: N/A
   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 is a 10x10 pixel shift designed to allow for the rejection of most SBC detector artifacts, including a horizontal strip caused by a bad anode.
     Pattern_Number: 31
       Pattern_Type: ACS-SBC-DITHER-LINE
    Pattern_Purpose: DITHER
   Number_Of_Points: 2
      Point_Spacing: 0.473
       Line_Spacing: N/A
   Coordinate_Frame: POS-TARG
     Pattern_Orient: 44.74
Angle_Between_Sides: N/A
     Center_Pattern: NO
POS TARG equivalent:  0.000,  0.000
                      0.336,  0.333


The following is an integer 2-point hot pixel dither pattern.
     Pattern_Number: 30
       Pattern_Type: ACS-SBC-DITHER-LINE
    Pattern_Purpose: DITHER
   Number_Of_Points: 2
      Point_Spacing: 0.095
       Line_Spacing: N/A
   Coordinate_Frame: POS-TARG
     Pattern_Orient: 44.74
Angle_Between_Sides: N/A
     Center_Pattern: NO
POS TARG equivalent:  0.000,  0.000
                      0.067,  0.067


The 2-point sub-pixel dither pattern.
     Pattern_Number: 32
       Pattern_Type: ACS-SBC-DITHER-LINE
    Pattern_Purpose: DITHER
   Number_Of_Points: 2
      Point_Spacing: 0.099
       Line_Spacing: N/A
   Coordinate_Frame: POS-TARG
     Pattern_Orient: 32.37
Angle_Between_Sides: N/A
     Center_Pattern: NO
POS TARG equivalent:  0.000,  0.000
                      0.084,  0.053


The 3-point sub-pixel dither pattern...
     Pattern_Number: 33
       Pattern_Type: ACS-SBC-DITHER-LINE
    Pattern_Purpose: DITHER
   Number_Of_Points: 3
      Point_Spacing: 0.110
       Line_Spacing: N/A
   Coordinate_Frame: POS-TARG
     Pattern_Orient: 44.71
Angle_Between_Sides: N/A
     Center_Pattern: NO
POS TARG equivalent:  0.000,  0.000
                      0.078,  0.078
                      0.157,  0.156


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