
  resid [-im time] [-X] [-l] (photometry file)

  plot the photometry residuals for a photometry database file. 
  For every star in the database, the average magnitude is plotted 
  vs the difference between the average magnitude and each existing 
  measurement for that star.  

  -l		automatically set the plot limits.
  -X		plot residual divided by photometric error
  -im time	only plot the residuals for one of the images 
		in the database, specified by the obseravation time.
