Data Taking Plans

[Tom Droege <tdroege2@earthlink.net>]

I have been digesting all the data analysis.  Sigh!  I have also been doing 
analysis of my own.  Just looking at lots of data analyzed different ways.

The bad news is that nothing seems to change the error level very much.  We 
are at about 0.1 mag at mag 12 and go into a noise floor of about 0.025 mag 
at mag 10.   The big disappointment was when I installed the focus 
stiffeners and was able to get nice round stars with a good focus.  It made 
no noticeable difference.  One can manipulate the data to make this a 
little better, but this is really cheating.  For example, if we always 
measure a star in the same position in the frame, then we can get the error 
down below 0.01 mag for some stars.  This is about a factor of two worse 
than surveys like ASAS.  Why?  Well, other surveys are operated with high 
class equipment at clear sites.  I mostly think that the difference is due 
to the site.  We shall see if ARNE and ROB can do better than I can.

The good news is that this is probably good enough for a useful survey.  I 
can do a nice job covering stars from mag 8 to 12.5 in V.

I plan to always measure a star with the telescope pointing in exactly the 
same place.  I have started such a survey with TOM1 and have been 
collecting data since November 02.  I get everything that crosses the 
zenith once in V and I per night.  I can already see variable stars in this 
data.  I already have 2-3 million measurements.  This may do somewhat 
better than the above as relative photometry.

I am going to concentrate now on operating procedures and just take and 
process data.

I am slowly getting my network working so that I will be able to store and 
process the data from TOM1, TOM2, and TOM3 while sitting in my comfy 
office.  I am working on software that will discard bad data.  This allows 
me to just turn on at dusk and take data regardless of where the moon 
happens to be sitting.  The software will then discard frames with too much 
moon or clouds.

Tom Droege