Good Board Stack

["Thomas Droege" <tdroege2@earthlink.net>]

The good board stack now stands at 2.  The "I don't know" stack is about
45.  So there is a lot of work to be done to transfer boards from one stack
to the other.  The work has started.  Once I get to 4 or 5 of each type in
the good stack, I will start to build cameras. 

This will all lead to construction of Mark Vs come spring or so.  

The plan is still to get a lot of spares, go through the TOMs and bring
each up to a standard configuration, and then design an operating procedure
for the production run.  

While working on the camera I found that there was a big capacitor where a
little one should be.  I had put it in for a test and it somehow got put in
all the cameras.  This is not a big problem, but can cause a slope in the
background.  All effects should be removed by normal dark and flat
corrections.   I think this is not the cause of the top to bottom gain
variation, but it could be.  I can't even imagine how to test the problem.  

In any case, I will change all the cameras as I work on them.

I hesitate to bring this up, but I will anyway.

In the past, I have prepared new darks and flats about once a month. 
Looking at them, they repeat well within the noise unless I have done
something.  The plan for future running is to continue doing this.  My
thinking is to do a maintenance during the time of the full moon.  The idea
is to dust/clean the lenses, and do darks and sky flats (before moon rise).
I know that it is standard ritual to do flats every night.  These take a
lot of time, and don't contribute anything.  Likewise the cameras are
temperature stabilized and darks are constant.  What does affect both are
the outside light conditions.  At my location these change constantly. 
There is no way to correct for when my neighbors decide to brighten up the
night sky.  These are much more a factor than "good" darks and flats.  So
why even try to do them every night?  The only reason that I can think is
that "every one does them" so I will be criticized if I don't.  But they
are useless.  Comments, anyone?

Tom Droege


Tom  Droege Jennifer Malpass
tdroege2@earthlink.net