% @(#)tests_ccd.hlq	1.1 (ESO-SDAG) 8/4/95 14:11:05
%++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
%.COPYRIGHT  (c)  1994 European Southern Observatory
%.IDENT      tests_ccd.hlq
%.AUTHOR     RHW, SDAG/ESO
%.KEYWORDS   MIDAS, ccd package, shutter, testing
%.PURPOSE    On-line help file for the command: TESTS/CCD
%.VERSION    940621 RHW created
%---------------------------------------------------------------------
\se
SECTION./CCD
\es\co
TESTS/CCD                                                     21-Jun-1994 RHW
\oc\su
TESTS/CCD in_frm1 inf_frm2 [out_frm] n_exp [dec_fac]
	Find the shutter error distribution
\us\pu
Purpose:    
	Find the shutter error distribution
\up\sy
Syntax:     
	TESTS/CCD in_frm1 in_frm2 [out_frm] n_exp [dec_fac]
\ys\pa
        in_frm1 = input frame containing the long flat exposure which the 
                  shutter opened and closed N times. No default.
\ap\pa 
        in_frm2 = input frame contained a long normal flat exposure.
                  No default.
\ap\pa 
        out_frm = output frame containing the shutter error image. Default
                  is SHERR.
\ap\pa
        n_exp =   number of short exposures in the first input frame. 
                  No default.
\ap\pa
        dec_fac = decimation factor for frame size reduction. Default is 16.
\ap\no
Note:
        The command determine the accuracy of the shutter. If in_frm1 has a 
        total reported exposure time of t1 seconds, and the shutter is opened 
        and closed n_exp times (including the beginning and end of the 
        exposure) and img2 has a total exposure time of t2 seconds, and the 
        shutter is only opened and closed once, then the final shutter error 
        frame out_frm is determined by:
             out_frm = (in_frm2*t1 - in_frm2*t2)/(in_frm1 - N*in_frm2).\\
        The shutter error frame is resampled where each pixel of the output 
        frame is the median of a dec_fac x dec_fac pixels area of the input 
        frame. 
\\
        An image and a contour plot of the error frame are stored in the 
        files `out_frm.bdf', `out_frm'.ps and `out_frm'_cont.ps respectivily.
\on\see
See also:   
        SET/CCD, SHOW/CCD
\ees\exs
Examples:
\ex
        TESTS/CCD shut1 shut2 ? 16
        Determine the shutter error from the frame shut1 and shut2. Use
        a median rebinning with a decimation factor 16. The default name 
        for the shutter error frame will be used. The contour plot is stored
        in the frame SHERR_cont.ps; the image is in file SHERR_displ.ps.
\xe \sxe