From: stephanie snedden
Subject: Re: 2.5m obslog 20070818 (MJD 54331)
Date: Sun, 19 Aug 2007 12:38:45 -0600
It is usually an r camera that has (S/N)^2
> The documentation under "Spectroscopy: Deciding if a plate is done"
> lists the
> usual criteria for declaring a SEGUE bright done:
>
> SEGUE (The bright plates)
> Summed (S/N)^2 > 15 in BOTH b1 and b2
>  **OR**
> Summed (S/N)^2 > 30 in either b1 OR b2
>
> but, it also discusses what to do if a camera is
> "(S/N)^2  bright plates,
> even under good observing conditions. It is permitted if other cameras
> are getting (S/N)^2 > 2. In that case, you would use the summed (S/
> N)^2 > 30
> in b1 or b2."
>
> We ran into confusion here because it doesn't specify whether or
> not it makes
> a difference as to which camera is  r1 was  and that was for every exposure.  So if it doesn't matter that r1
> was  time because we were able to accumulate b1 and b2 > 15.0, then this
> plate can
> be considered done.  Our hunch is that the documentation is saying
> that the if
> one of the blue cameras is  30
> criterion,
> because the blue camera values are the deciding factor under the
> conditions
> where there are no cameras  clarification on this subject.