pro wfpc2_read,filename,chip1,header1,chip2,header2, $ chip3,header3,chip4,header4,num_chip=num_chip, $ trim=trim, path = path,batwing=batwing ;+ ; NAME: ; WFPC2_READ ; ; PURPOSE: ; Read WFPC2 images in either FITS or STSDAS format into IDL variables. ; ; EXPLANATION: ; This a versatile procedure for reading Wide Field Planetary Camera 2 ; (WFPC2) images. One can read either FITS or STSDAS format, and specific ; chip or chips. One can also read all four chips into a "batwing" mosaic-- ; so-called because the PC chip (chip 1) has a plate scale of 0.045", while ; the other three WF chips have a plate scale of 0.1" ; ; CALLING SEQUENCE: ; WFPC2_READ,filename,chip1,hdr1,chip2,hdr2,chip3,hdr3,chip4,hdr4 ; or ; WFPC2_READ,filename,chip,hdr, NUM_CHIP = [1,2,3,4], [/TRIM, PATH = ] ; or ; WFPC2_READ,filename,image,hdr,/BATWING ; ; INPUTS: ; filename - Name of FITS or STSDAS file with a stack of images from ; the four WF/PC-2 chips, followed by a FITS ASCII ; table with header parameters for each chip. If the file ; name extension ends in 'h' then it is assumed to be an ; STSDAS file. If no extension is supplied, and the file is ; is not found, then WFPC2_READ first tries appending a '.fits' ; extension, and then tries appending a '.c0h' extension. ; ; INPUT KEYWORD PARAMETERS: ; NUM_CHIP - Integer scalar or vector, subset of 1, 2, 3, 4, specifying ; particular chip numbers to read. Outputs will be in same ; order as specification of subset. (See Example 2.) ; /TRIM - If set, trim off areas with no image and re-orient so that ; all the chips have a common orientation suitable for insertion ; into "bat-wing" mosaic (no image distortion removal, however). ; PATH - scalar string specifying a !PATH-like list of directories ; in which to search for the file. Default is to look only ; in the current directory. ; /BATWING - Return a 1600 x 1600 array containing all four chips in a ; "bat wing" mosaic formation. This image is mainly for ; display purposes, since the PC chip is compressed to match the plate ; scale of the WF chips. In addition, a small astrometry error ; is introduced since chips do not have the same rotation, nor ; are they aligned at the integer pixel level. ; OUTPUTS: ; chipN - 800 X 800 image from chip N. If /TRIM is set then the output ; size is somewhat smaller (e.g. 756 x 757) ; headerN - Individual FITS header for chip N with correct astrometry. ; ; PROCEDURES USED: ; For FITS I/O: FITS_CLOSE, FITS_OPEN, FITS_READ ; For STSDAS I/O: EXTGRP, FTGET(), SXOPEN, SXREAD() ; Other procedures: CHECK_FITS, FDECOMP, FIND_WITH_DEF(), FREBIN, HEXTRACT, ; HROTATE, SXADDHIST, SXADDPAR, SXPAR() ; EXAMPLE: ; (1) Read all four chips of the FITS file u2ou0201t_c0f.fits ; ; IDL> wfpc2_read,'u2ou0201t_c0f',c1,h1,c2,h2,c3,h3,c4,h4 ; ; (2) Note that supplying the .fits extension is optional. Now read only ; chips 1 (the PC chip) and 3. Trim off portions of the arrays where ; there is no image. ; ; IDL> wfpc2_read,'u2ou0201t_c0f',c1,h1,c3,h3,num=[1,3],/trim ; ; (3) Note that with the /TRIM option the output chip sizes are no longer ; 800 x 800 but odd sizes such as 770 by 753. Now read all 4 chips ; into a 1600 x 1600 "batwing" mosaic ; ; IDL> wfpc2_read,'u2ou0201t_c0f',im,h,/batwing ; ; MODIFICATION HISTORY: ; Written by W. Landsman, Raytheon STX, for IDL V5.0 June 1998 ; Based on code by Robert Hill, Raytheon STX ; Better astrometry of PC image in "batwing" configuration, W. Landsman ; August 1999 ;- if N_params() LT 2 then begin print,'Syntax:' print,' WFPC2_READ,filename,chip1,hdr1,chip2,hdr2,chip3,hdr3,chip4,hdr4' print,' or' print,' WFPC2_READ, filename,chip,hdr, NUM_CHIP =[1,2,3,4], [/TRIM, PATH=]' print,' or' print,' WFPC2_READ,filename,image,hdr,/BATWING, PATH=]' return endif ; EXTPARS gives the region of each chip containing valid data. ROTPARS ; gives the IDL ROTATE parameter to apply to each chip to give them a common ; orientation. X1 and Y1 give the starting pixel of each chip in the ; "batwing" mosaic. extpars = [[44, 799, 52, 799], [ 0, 773, 46, 799], $ [ 0, 769, 0, 752], [44, 799, 0, 756] ] rotpars = [0, 1, 2, 3] x1 = [800,26,30,800] y1 = [800,800,47,43] if N_elements(num_chip) EQ 0 then $ if (N_params() LE 3) and not keyword_set(BATWING) then num_chip = 1 if N_elements(num_chip) GT 0 then num_c = num_chip $ else num_c = [1,2,3,4] if keyword_set(batwing) then begin chip1 = fltarr(1600,1600) num_c = [1,2,3,4] trim = 1 endif Nout = N_elements(num_c) ; If the specified file is not found, try adding a '.fits' and then a '.c0h' ; extension if N_elements(PATH) EQ 0 then path = '' a = FIND_WITH_DEF(filename, path, '.fits,.c0h') FDECOMP, a[0], disk, dir, fname, ext if strlowcase(strmid(ext,2,1) EQ 'h') then begin ;SDAS format SXOPEN, 1, a[0], htab for i = 0, Nout-1 do begin j = num_c[i] - 1 thischp = SXREAD(1, j, par) thishdr = htab EXTGRP, thishdr, par ;Insert group parameters into FITS header if keyword_set(TRIM) then begin HROTATE, thischp, thishdr, rotpars[j] HEXTRACT, thischp, thishdr, extpars[0,j], extpars[1,j], $ extpars[2,j], extpars[3,j], /SILENT endif ii = strtrim(i+1,2) jj = strtrim(j+1,2) sxaddhist,'----------------------------------------------------------', $ thishdr sxaddhist,' WFPC2_READ: ' + systime(), thishdr sxaddhist,' Header parameters for chip ' + jj + $ ' replaced from group parameters', thishdr if keyword_set(batwing) then begin if i EQ 0 then $ chip1[x1[0],y1[0]] = FREBIN(thischp,345.7,342,/total) else $ chip1[x1[i],y1[i]] = thischp if i EQ 3 then begin crpix = sxpar(thishdr,'CRPIX*') sxaddpar, thishdr, 'CRPIX1', crpix[0] + x1[3] sxaddpar, thishdr, 'CRPIX2', crpix[1] + y1[3] header1 = thishdr CHECK_FITS,chip1,header1,/update,/silent,/FITS endif endif else begin tst = execute('chip' + ii + '= temporary(thischp)') tst = execute('header' + ii + '= thishdr') endelse endfor endif else begin FITS_OPEN, a[0], fcb if Nout EQ 1 then begin ns = fcb.axis[0,0] nl = fcb.axis[1,0] i1 = (ns*nl)*(num_chip-1) i2 = i1 + ns*nl-1 FITS_READ, fcb, chip1, h, first=i1, last=i2 chip1 = reform(chip1,ns,nl) endif else FITS_READ,fcb,d,h ; Now read the first FITS extension which contains the ASCII table, giving ; separate astrometry parameters for each of the four chips. FITS_READ, fcb, dtab, htab, /no_pdu tf = sxpar(htab,'TFIELDS') name = sxpar(htab,'TTYPE*') fmt = sxpar(htab,'TFORM*') comment = strarr(tf) for j=0,tf-1 do comment[j] = sxpar(htab,name[j]) if fcb.axis[1,0] LT max(num_c) then begin message, /inf,'Image ' + filename + ' contains only PC image' num_c = fcb.axis[1,0] endif FITS_CLOSE, fcb ftinfo,htab,ft_str for i = 0, Nout-1 do begin cn = num_c[i] cn_0 = cn - 1 cn_str = strtrim(num_c[i],2) cn_arg = strtrim(i+1,2) hdr = 'header' + cn_arg chp = 'chip' + cn_arg thishdr = h sxaddhist,'----------------------------------------------------------', $ thishdr sxaddhist,' WFPC2_READ: ' + systime(), thishdr sxaddhist,' Header parameters for chip ' + cn_str $ + ' replaced from table.', thishdr for j=0,tf-1 do begin value = ftget(ft_str,dtab,j+1,cn_0) sxaddpar, thishdr,name[j],value[0],comment[j],format=fmt[j] endfor if nout GT 1 then begin thischp = d[*,*,cn_0] CHECK_FITS, thischp, thishdr, /fits, /update, /silent if keyword_set(trim) then begin HROTATE, thischp, thishdr, rotpars[cn_0] HEXTRACT, thischp, thishdr, extpars[0,cn_0], extpars[1,cn_0], $ extpars[2,cn_0], extpars[3,cn_0],/SILENT endif if keyword_set(batwing) then begin if i EQ 0 then $ chip1[x1[0],y1[0]] = FREBIN(thischp,345.7,342.0, /total) else $ chip1[x1[i],y1[i]] = thischp if i EQ 3 then begin crpix = sxpar(thishdr,'CRPIX*') sxaddpar, thishdr, 'CRPIX1', crpix[0] + x1[3] sxaddpar, thishdr, 'CRPIX2', crpix[1] + y1[3] header1 = thishdr CHECK_FITS, chip1, header1, /update, /silent, /FITS endif endif else begin tst = execute( chp + " = temporary(thischp)") tst = execute( hdr + " = thishdr") endelse endif else begin header1 = thishdr CHECK_FITS, chip1, header1, /fits,/update,/silent if keyword_set(TRIM) then begin HROTATE, chip1, header1, rotpars[cn_0] HEXTRACT, chip1, header1, extpars[0,cn_0], extpars[1,cn_0], $ extpars[2,cn_0], extpars[3,cn_0],/silent endif endelse endfor endelse return end