; Routine to find image motion versus time for PR110L observations
; using red leak pile-up
;
; list of PR110L observations with approximate centers of red leak without
; contamination by observed wavelength spot
;
	list = 8800+[33,34,35,36,37,38]
	
	xc = 276 & yc = 540
	n = n_elements(list)
;
; determine x profiles
;
	xprofiles = fltarr(31,n)
	for i=0,n-1 do begin
		acs_read,list(i),h,d
		sub = d(xc-15:xc+15,yc-6:yc+6)
		tvscl,rebin(sub,310,130,/sample)<100
		xprofiles(*,i) = total(sub,2)
	end

;
; compute cross correlation of spectra from first
;
	xcorr = fltarr(n)
	for i=0,n-1 do begin
		cross_correlate,xprofiles(*,0),xprofiles(*,i),off
		xcorr(i) =  off
	end
;
; Get observation times
;
	dbext,list,'expstart,exptime',start,integ
	time = start + integ/60.0d0/60.0d0/24.0d0/2.0
;
; fit by straight line
;
	time = (time - time(0))*24
	c = poly_fit(time,xcorr,1,fit)
;
; Plot results
;
	set_plot,'ps'
	device,/land,file='PR110L_x_motion.ps'
	set_xy,-0.5,1.5
	!p.thick=3
	!x.thick=3
	!y.thick=3
	!p.font=0
	!p.title='PR110L Image Motion'
	!x.title='Time Since First Observation (Hours)'
	!y.title='X - Image Motion (pixels)'
	plot,time,xcorr,psym=4,symsize=2
	oplot,time,fit
	device,/close	
	print,c
;    -0.087360157
;     -0.10340273
end