deletions | additions       diff --git a/Now_its_time_time.tex b/Now_its_time_time.tex  index 37bbcaa..9ef96cd 100644  --- a/Now_its_time_time.tex  +++ b/Now_its_time_time.tex 
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You should have four files full of photometric information. All we  really want is the summed, sky-subtracted pixel values for each   star. Ask {\color{blue}Ask  your demonstrator how to extract the column containing the pixel values, and transfer them across to the Excel on  a Windows PC. PC.}  {\color{red}Run   \begin{verbatim}  > ../extract_params.pl OUTPUT.FILE  \end{verbatim}  and transfer the output files across to the Excel on  the Windows PC.}  \subsection{The Nature of the Stars}