Date: Wed, 16 May 2001 20:38:29 -0400 (EDT)
From: jeg@astro.Princeton.EDU
Subject: Re: Pointing with the spectrograph (was 2.5-m ObsLog 20010515 (MJD 52045))
I think it very likely indeed that we will want an instrument block
per cartridge. I do not know what the nominal tolerances are, but there
are a LOT of parts between the kinematics and the plate, and I would
be very surprised if the plate is located better than 10 mils or so
with respect to the kinematics. That is 250 microns, about 4 arcseconds,
or the radius of the guide fibers, and a big chunk of the 10 arcsecond
pointing accuracy.
Thanks for pointing this out, Chris.
--jim