pro zzalign
  If ( !version.os eq 'Win32' ) Then st = '\'

  If ( !version.os eq 'linux' ) Then st = '/'

  Print, 'Where is the sav file after rotation?'

  dir_read = DIALOG_PICKFILE( /DIRECTORY )

   file_mkdir,dir_read+'aln'
  dir_write = dir_read+'aln'+st

  list = file_search(dir_read + '*aln.fts',count=nn)
   pos = STRPOS(list[0], 'aln.fts')
   spos = Strpos( list[0], st, /reverse_search )
   sn = pos - spos
  listname = STRMID(list, spos+1, sn-1)

  img = readfits(list[0],head)
  WRITEFITS, dir_write+listname[0]+'aln.fts', img, head
   sz = size(img)
   print,sz


   xtvscl,img
   print,'Selet the area used for alignment'
   box_cursor,x,y,dx,dy
   imgg = fltarr(dx,dy)
   imgg1 = fltarr(dx,dy)
   imgg=img[round(x):round(x)+dx-1,round(y):round(y)+dy-1]
   j = 0
   for i = 1,nn-1 do begin
       print,i
       img =readfits(list[i],head)
       imgg1 = img[round(x):round(x)+dx-1,round(y):round(y)+dy-1]
       offset = ch_alignoffset(imgg1,imgg,cor)
       print,cor
       if cor gt 0.6 then begin
           img=ch_shift_sub(img,-offset(0),-offset(1))
           imgg = img[round(x):round(x)+dx-1,round(y):round(y)+dy-1]
           WRITEFITS, dir_write+listname[i]+'aln.fts', img, head
           j=j+1
       endif
  endfor

print,nn,j+1



end