Date: Fri, 15 Sep 2006 14:22:26 -0600 (MDT)
From: Jurek Krzesinski
Subject: Re: checksum warnings in 2.5m obslog 20060914 (MJD 53993)
On Fri, 15 Sep 2006, Constance Rockosi wrote:
> Yes, I am pretty sure he stuffs in new (or maybe alters)
> keywords in the headers.
> --connie
He told me that he does change the fits file headers but those are
files grabbed directly from the pool. The files which are stored on
sdssfields probably do not have headers changed. When we
accidently deleted the data from photo/doi directory, Mamoru said that he
cannot use the data stored already on sdssfields, because these have fits
headers which are not the same he uses and there is no information in them
he needs for the reduction. Can it be that goStare mode for imager
produces fits headers which do not have proper information for the checsum?
   Jurek
>
> On Fri, Sep 15, 2006 at 11:45:07AM -0500, Eric H. Neilsen, Jr. wrote:
> > Kurt,
> >
> > The frame catcher checks checksum in the fits header using the cfitio
> > library, which uses the same checksum pseudo-standard the DA does. The
> > murmur message quoted below means that the checksum in the header did
> > not match the data. We need to understand what happened here.
> >
> > All of the examples you list look like they were produced by Mamuro's
> > tests. It's hard to be certain, because these tests do not get written
> > up in the night log. I know the code he uses to collect data branched
> > from the IOP code usually used many years ago, but know very little
> > about what it actually does. Perhaps he does something to the data or
> > header after the checksum is calculated but before the frameCatcher
> > copies it?
> >
> > 	-Eric
> >
> >
> > Kurt Biery wrote:
> > > I checked recent spectro and PT frames, and they seem to be OK.  For
> > > imager frames, the FrameCatcher complains if it finds ones with bad
> > > checksums.  I see lots of messages in recent murmur logs like the
> > > following for runs 6306, 6307, 6308, 6309, 6315, 6322, 6324, 6326, 6328,
> > > 6333, 6335, 6337, 6339, 6339, 6341, 6343, and 6346.  Maybe these
> > > "invalid frames" are expected based on a special type of running?
> > >
> > > 2006-09-13 16:46:26Z sdssfiles1 frameCatch TEXTONLY Invalid frame
> > > /data/photo/frames/53991/6339/1/idRR-006339-r1-0072.fit processed anyway
> >
> > DSS DSS DSS DSS DSS  Digital Sky Survey DSS DSS DSS DSS DSS DSS
> > DSS *** The information posted to SDSS mailing lists is proprietary ***
> > DSS  This is message 3091 in the sdss-25mlog archive, URL
> > DSS         http://www.astro.princeton.edu:81/sdss-25mlog/msg.3091.html
> > DSS  The index is at http://www.astro.princeton.edu:81/sdss-25mlog/INDEX.html
> > DSS  To join/leave the list, go to
> > DSS         http://www.astro.princeton.edu:81/cgi-bin/mailinglists.pl/show_subscription?list=sdss-25mlog
> > DSS  To post a message, mail it to sdss-25mlog@astro.princeton.edu
> > DSS
> > DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS
> >
> > !DSPAM:450ad8a513270230409692!
> >
>
> DSS DSS DSS DSS DSS  Digital Sky Survey DSS DSS DSS DSS DSS DSS
> DSS *** The information posted to SDSS mailing lists is proprietary ***
> DSS  This is message 3092 in the sdss-25mlog archive, URL
> DSS         http://www.astro.princeton.edu:81/sdss-25mlog/msg.3092.html
> DSS  The index is at http://www.astro.princeton.edu:81/sdss-25mlog/INDEX.html
> DSS  To join/leave the list, go to
> DSS         http://www.astro.princeton.edu:81/cgi-bin/mailinglists.pl/show_subscription?list=sdss-25mlog
> DSS  To post a message, mail it to sdss-25mlog@astro.princeton.edu
> DSS
> DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS DSS
>