Date: Tue, 01 Apr 2008 10:12:24 -0500 (CDT)
From: Stephen Kent
Subject: Re: 2.5m obslog 20080331 (MJD 54557)
>
> We noticed that plate 2874 expires while it is at an alt of 42.5
> degrees and still rising.  It starts very low at ~32 degrees.  So we
> suspect the window in the database may be wrong but since we had a
> higher priority plate available when it expired we switched to it.
The plate database is correct.  This plate was designed to be observed at
an easterly hour angle.  Note that if it were designed for observing on
the meridian, it would be competing against the large number of existing
SEGUE and Legacy plates available at the same time.
The plate layout program tries to design plates to be observable over as
wide a range of sidereal times as possible, so this means some plates are
designed for observing at rather large hour angles.  This strategy was
implemented back when we only had legacy plates that could be observed in
an hour.  Probably not ideal for seguefaint plates, but no strategy is
bound to be perfect.
Brian Yanny asked that plate 2874 be given high priority, so please try to
finishi it if you can.
Thanks! Steve