Reduction pipeline

[Doug Welch <welch@physics.mcmaster.ca>]

Folks,

I will wade in several times today on various points, as time
allows. I agree whole-heartedly with Arne's comments about IRAF
w.r.t. other reduction packages. It is available for free, is
very well supported, comes on many platforms, and has large amounts
of useful documentation - such as "cookbooks" - for the newcomer.
It is quite thoroughly debugged compared to other packages and
doesn't suffer from the "programmer gets hit by a bus or loses
interest" problem. That is, there are no "single point failures"
if IRAF is adopted - practically any astronomical institution
has local IRAF expertise. That is, a knowledge base exists which
is, hands down, greater than all of its competitors combined.

It is true that you can probably write more compact code, use less
disk space, and have a shorter learning curve with other programs.
You can, of course, reduce data successfully using a dozen different
routines and techniques. Still, it is my opinion that if one needed
to sit down with a script in 5 years to see what it did, or to pass
scripts to a new location or institution, IRAF scripts will be
in the "vernacular" and the others won't.

Cheers,
Doug