PROCEDURE: 10s

TITLE: SBC image stability test

CATEGORY: verification

PURPOSE: To determine and quantify if there are any end-to-end shifts or
drifts in the SBC between the coronographic arm and the SBC detector.

FREQUENCY: Run continuosly while the instrument makes a thermal
transition during the ACS thermal vacuum tests.

DETECTOR: SBC

PREREQUISITES: Coronographic arm in place.  Safe-open with arm in place.
Count rate set to 0.3Hz/pixel using the STUFF attenuators.

HARDWARE REQUIREMENTS: STUFF + PtNe1 + micro-mirror array.
Coronographic arm must not be moved during test.  Filter wheel should
also not move.

SOFTWARE REQUIREMENTS: acs_gain, acs_stats

COMMAND MODE: SMS(?)

PROCEDURE/EXPOSURES:  
  F150LP  --> countrate = ~0.3 Hz/pixel
  1-16.   300s   external F150LP   
	         Dump data
 17-32.   300s   external F150LP   
	         Dump data
VARIANTS: 

TOTAL EXPOSURES: 32

TOTAL TIME: setup + 32*overhead + 2*dump + 2.67hr = 3.40hr
    Assume setup = 600s, overhead = 41s (from previous SMS's), dump = 358s

ANALYSIS:
    * collapse column and row cuts through central coron. spot
    to 1d, cross-correlate with initial column and row cuts,
    to derive horizontal  and vertical shifts.
    * plot shifts as a function of environmental temperature,
    and time.  
    * note any drifts or sudden shifts.