% @(#)testfaccd.hlq 17.1.1.1 (ESO-SDAG) 01/25/02 17:49:46 %++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %.COPYRIGHT (c) 1994 European Southern Observatory %.IDENT testfaccd.hlq %.AUTHOR RHW, SDAG/ESO %.KEYWORDS MIDAS, ccd package, flat, testing %.PURPOSE On-line help file for the command: TESTFA/CCD %.VERSION 940620 RHW created %.VERSION 940816 RHW split into single subroutines %--------------------------------------------------------------------- \se SECTION./CCD \es\co TESTFA/CCD 20-Jun-1994 RHW \oc\su TESTFA/CCD in_cat [out_id] [meth] [area] [exp_ran] [thresh] Do a series of tests on a catalogue of low count flat frames \us\pu Purpose: Do a series of tests on a catalogue of low count flat frames \up\sy Syntax: TESTFA/CCD in_cat [out_id] [meth] [area] [exp_ran] [theshold] \ys\pa in_cat = input (with the extension .cat) catalogue of frames to be combined; no default. \ap\pa out_id = output identifier for the output of the test prodedure. All output (i.e. frames, listings and plots) will start with this identifier. Default is FLAT. \ap\pa meth = combining method for creation of the master low-count- level flat. Possible methods are: sum - simple sum of all input input images;\\ ave(rage) - combined by averaging;\\ median - combining by medianing each pixel;\\ min(reject) - reject the min value from the average;\\ max(reject) - reject the max value from the average;\\ minmax(reject) - reject min and max from the average;\\ sig(clip) - sigma clipping to each pixel;\\ avsig(clip) - sigma clipping with minmax rejection;\\ In case clipping algoritms are used the keyword BS_CLP will be read to get the clipping factors.\\ Default is the average sigma clipping method. In case clipping algoritms are used the keyword FF_CLP will be read to get the clipping factors. \ap\pa area = area of the input frames in which the pixels will be considered. Default is the whole image area. \ap\pa exp_ran = Range of exposure times to be combined into the master flat field. The exposure time is normally recored in the descriptor O_TIME(7). Default 0,5 seconds \ap\pa thresh = fraction of the median count rate in the master flat frame below which intensities are considered to be generated from cold pixels on the detector. Default is 0.20. \ap\no Note: This command requires the keyword BIASMEAN and BIASSIGM to be filled and hence should be executed after the commands TESTBA/CCD or TESTB5/CCD. The command will do the following two tests on the frames in the input catalogue:\\ Test F1: Creation of the combined flat frame, using only those flat frames in the input catalogue that have exposure times falling within the allowed range. The combined flat is corrected for the bias offset. The bias offset is taken from the keyword BIASMEAN filled by the command TESTB/CCD. The combined flat is loaded on the display.\\ Test F2: Thereafter all pixels in the stacked master flat frame that show values less than thresh times the median counts in the frame are listed. Only pixels within the area contained in `area' are considered and repetitions of cold pixels in the increasing y coordinate are not listed. \\ The command will stored the outputs in a number of ascii and postscript files (preceding by the identification string out_id):\\ `out_id'.bdf: the combined low count flat;\\ `out_id'.ps: postscript file with an image of the combined low count flat;\\ `out_id'_coldpix.tbl: MIDAS table containing the cold pixels;\\ `out_id'_coldpix.txt: a ascii tablke containing the cold pixels.\\ \\ The command checks for the presence of the combined flat frame and does not recompute the frame if is is already present. \\ Single tests on the flat frames can be executed using the commands TESTFn/CCD with n = 1 or 2. \\ For more details about the various combining methods, please refer to the CCD Chapter in Volume B of the ESO-MIDAS Users' Guide. \on\see See also: TESTFn/CCD, SET/CCD, SHOW/CCD, TESTBA/CCD, COMBINE/CCD, FILTER/MEDIAN, FIND/PIXEL \ees\exs Examples: \ex TESTFA/CCD ff_cat.cat FMASTER median 5,20 0.20 Run the complete test procedure on the frames in the catalogue ff_cat. Combine all frames with exposure times between 5 and 20 seconds using the median algorithm. Subtract the bias offset and find all cold pixels with less than 20 percent of the median pxiel value in the combine flat. \xe \sxe