Forum der Vereinigung der Sternfreunde

Hi I am working through reducing my echelle spectra with IRAF but I have two points I can't solve.

My horizontal spectra are unfortunately captured with red on the left and blue on the right so I would like to flip them left/right.
I have found "imtranspose" which I can use to do two clockwise turns which solve the left right issue but inverts the spectra. I am not sure this matters but is there a way to flip an image in IRAF.

Also I need to use my own calibration line list but can't find a clear description of the format could some one give me an example please.

Thanks in advance Andrew

Hello Andrew
both are no real problems.
When you want to flip a 1D spectrum use scopy with w2 < w1
http://iraf.net/irafhelp.php?val=scopy&help=Help+Page

For 2D spectrum use imcopy
cl> imcopy dev$pix[*,-*] pix1 # flip the rows
cl> imcopy pix1[*,-*] pix1 # flip the rows in place
http://bishop.astro.pomona.edu/Penprase ... g-add.html

An example for a calibration line list you will find attached. This contains the Ne-lines. Use the first two columns.
Cheers
Christian

Thanks Christian, it is such a vast system it is hard to find what you need.

Input much appreciated.

Regards Andrew

Hello Andrew
in most cases the help command is helpful.
When you want to know what e. g. scopy does print 'help scopy' and the help text appears in your input window. With 'help scopy > scopy.txt' you can save the help text in a text file. At the end are mostly a variety of examples.
imcopy and scopy are very powerful commands as well as splot. It pays to take time for reading the the help text of the most frequently used commands.
Cheers Christian

Thanks Christian, I do use the help command but it never occurred to me that imcopy could do what I wanted! I don't have a good mental model of how IRAF is structured yet.

Fortunately I only need a small subset of IRAF and with help from yourself and other I am nearly there.

Regards Andrew