PRO checkvar,filename,nowin=nowin

; getsig,1993,12,8,mask0,mask1

; mask=mask1	; depends on which camera we want to look at

mk,mask
mask(8:15,64:103)=1
mask(16:23,48:127)=1
mask(24:31,40:151)=1
mask(32:39,32:167)=1
mask(40:47,24:175)=1
mask(48:55,16:183)=1
mask(56:199,8:191)=1
mask(200:207,8:191)=1
mask(208:215,16:183)=1
mask(216:223,24:175)=1
mask(224:231,32:159)=1
mask(232:239,40:143)=1
mask(240:247,56:111)=1
mask(64:199,192:199)=1
mask(72:183,200:207)=1
mask(96:167,208:215)=1
mask(200:207,8:15)=0
wmask=WHERE(mask)

OPENR,un,'save/'+filename,/GET_LUN
stat=FSTAT(un)
nimages=stat.SIZE/66048L
FREE_LUN,un

filenum=LONG(STRMID(filename,0,8))
filt=filenum MOD 10 & filenum=filenum/10
cam=filenum MOD 10 & filenum=filenum/10
day=filenum MOD 100 & filenum=filenum/100
month=filenum MOD 100 & filenum=filenum/100
year=filenum+1900
bgs=(STRLOWCASE(STRMID(filename,9,3)) EQ 'bgs')

x=FINDGEN(41)*10-200
itime=INTARR(4)
IF NOT KEYWORD_SET(nowin) THEN WINDOW,XSIZE=1024,YSIZE=512

FOR i=0,nimages-1 DO BEGIN
    getray,year,month,day,cam,filt,i,hb,im,bgs=bgs
    hd=gethd(hb)
    FOR j=0,3 DO itime(j)=hd.misc.tm.(j)
    bin8=stdsize(binf(im,8))
    spm=(im-bin8)*mask
    IF NOT KEYWORD_SET(nowin) THEN TVSCL,spm,(i MOD 8)
    y=HISTOGRAM(spm(wmask),MIN=-200,MAX=200,BIN=10)
    res=gaussfit(x,y,a)
    PRINT,itime(0:2),a(2),FORMAT='(3(I2.2,":"),F5.1)'
    k=GET_KBRD(0)
    IF k NE '' THEN GOTO,DONE
    ENDFOR

DONE:

END