SUBROUTINE OBSKPNO(IFKPNO)
C     PRELIMINARY KPNO SOLAR ATLAS BY BRAULT AND TESTERMAN
 
C     IFKPNO=1 NORMAL PLOT WEIGHT 1
C     IFKPNO=2 NORMAL PLOT WEIGHT 12
C     IFKPNO=3 NORMAL PLOT WEIGHT 12 PLUS 10X WEIGHT 1
C     IFKPNO=10+ABOVE  PLOT LIMB
C
      COMMON /PARAMS/IFLABL,IFABSO,IFCONT,IFGRID,IFDLIN,IFLOG,XSCALE,
     1               RMIN,WEAK,TOP,PANEL,CYCLES,WBEGIN,WEND,W1,W2,YTOP,
     2               HMAX,HMIN,IFMU,NOCALC,YSCALE,OFFSET,IFVAC,RMAX,
     3               WNEW1,WNEW2,SMOOTH,DOPOBS,DOPCALC,DOPTERR,NOPRNT,
     4               SCALOBS,ZEROOBS,RMIN2,RMAX2,XOFFSET,SCALOB2,AXISWT
      REAL*8 WBEGIN,WEND,W1,W2,RESOLU,RATIO,WNEW1,WNEW2,WAVEL
      DATA IREAD/0/
      INTEGER*2 ISPECT(500),LAMBDA,NORD,NSET,NREC
      IF(IREAD.EQ.1)GO TO 1
      OPEN(UNIT=60,SHARED,READONLY,TYPE='OLD',FORM='UNFORMATTED')
      IREAD=1
    1 CONTINUE
      IF(IFKPNO.GT.10)GO TO 30
      IF(IFMU.GE.2)GO TO 30
C     CENTER
      IF(W1.GT.1080.)RETURN
      IF(W2.LT.294.2)RETURN
      REWIND 60
      ISTART=0
      CALL WEIGHT(MINWT)
      NSKIP=W1*10.-2942.
      IF(NSKIP.GT.0)THEN
      DO 2 ISKIP=1,NSKIP
    2 READ(60)
      ENDIF
      IREAD=NSKIP
      XSAVE=100000.
      XSAVE1=100000.
      LAST=0
    3 READ(60)LAMBDA,NORD,NSET,NREC,ISPECT
      IREAD=IREAD+1
      IF(LAMBDA.LE.LAST)GO TO 3
      LAST=LAMBDA
      WAVE=FLOAT(LAMBDA)*.1
      ISTART=0
      IF(IFKPNO.GT.1)CALL WEIGHT(12)
      DO 14 I=1,500
      W=WAVE+FLOAT(I-1)*.0002
      W=W*(1.D0+DOPOBS/299792.458D0)
      IF(W.LT.W1)GO TO 14
      IF(W.GT.W2)GO TO 315
      X=(W-W1)*XSCALE*10.
      IF(ISPECT(I).GT.11000)ISPECT(I)=0
      S=FLOAT(ISPECT(I))/10000.
      S=(S-ZEROOBS)*SCALOBS
      Y=(S-RMIN)/(RMAX-RMIN)*3.125*YSCALE
      Y=AMAX1(Y,0.)
      IF(ISTART.EQ.0)THEN
      CALL JUMP TO (X,Y)
      IF(XSAVE.LT.X)CALL JUMP TO (XSAVE,YSAVE)
      ENDIF
      ISTART=1
      CALL LINE TO (X,Y)
   14 CONTINUE
      XSAVE=X
      YSAVE=Y
  315 ISTART=0
      IF(IFKPNO.LT.3.)GO TO 333
      CALL WEIGHT(MINWT)
      DO 324 I=1,500
      W=WAVE+FLOAT(I-1)*.0002
      W=W*(1.D0+DOPOBS/299792.458D0)
      IF(W.LT.W1)GO TO 324
      IF(W.GT.W2)GO TO 15
      X=(W-W1)*XSCALE*10.
      XNEW=X
      S=FLOAT(ISPECT(I))/10000.
      S=(S-ZEROOBS)*SCALOBS
      Y=(S-.9)/(1.0-.9)*3.125*YSCALE
      YNEW=Y
      IF(ISTART.EQ.0)THEN
      IF(Y.LT.0.)Y=0.
      GO TO 240
      ENDIF
      IF(YNEW.GE.0..AND.YOLD.GE.0.)GO TO 240
      Y=0.
      IF(YNEW.LT.0..AND.YOLD.LT.0.)GO TO 240
      IF(YOLD.LE.0.)GO TO 239
      X=XOLD+(XNEW-XOLD)/(YNEW-YOLD)*(0.-YOLD)
      GO TO 240
  239 X=XOLD+(XNEW-XOLD)/(YNEW-YOLD)*YNEW
  240 IF(ISTART.EQ.0)THEN
      CALL JUMP TO (X,Y)
      IF(XSAVE1.LT.X)CALL JUMP TO (XSAVE1,YSAVE1)
      ENDIF
      ISTART=1
      XOLD=XNEW
      YOLD=YNEW
      CALL LINE TO (X,Y)
  324 CONTINUE
      XSAVE1=X
      YSAVE1=Y
  333 IF(IREAD.LT.7950)GO TO 3
   15 CALL WEIGHT(MINWT)
      RETURN
C     LIMB
  30  IF(W1.GT.973.9)RETURN
      IF(W2.LT.367.6)RETURN
      REWIND 60
      ISTART=0
      CALL WEIGHT(MINWT)
      NSKIP=7950
      DO 21 ISKIP=1,NSKIP
   21 READ(60)
      IREAD=NSKIP
      NSKIP=W1*10.-3676.-10.
      IF(NSKIP.GT.0)THEN
      DO 22 ISKIP=1,NSKIP
   22 READ(60)
      IREAD=IREAD+NSKIP
      ENDIF
      LAST=0
   23 READ(60)LAMBDA,NORD,NSET,NREC,ISPECT
      IREAD=IREAD+1
      IF(LAMBDA.LE.LAST)GO TO 23
      IF(LAMBDA.GT.LAST+1)ISTART=0
      LAST=LAMBDA
      WAVE=FLOAT(LAMBDA)*.1
      DO 24 I=1,500
      W=WAVE+FLOAT(I-1)*.0002
      W=W*(1.D0+DOPOBS/299792.458D0)
      IF(W.LT.W1)GO TO 24
      IF(W.GT.W2)GO TO 25
      X=(W-W1)*XSCALE*10.
      S=FLOAT(ISPECT(I))/10000.
      IF(S.GT.2.)S=0.
      S=(S-ZEROOBS)*SCALOBS
      Y=(S-RMIN)/(RMAX-RMIN)*3.125*YSCALE
      Y=AMAX1(Y,0.)
      IF(ISTART.EQ.0)CALL JUMP TO (X,Y)
      ISTART=1
      CALL LINE TO (X,Y)
   24 CONTINUE
      IF(IREAD.LT.13997)GO TO 23
   25 CALL WEIGHT(MINWT)
      RETURN
      END