Data

[Tom Droege <droege@wwa.com>]

I got lots of pretty good data last night.  The focus was pretty good and
the sky pretty clear, and i took two CD ROMs full of data.  Most of it
where I sit at one declination and follow the sky for an exposure, then
rewind, then make another exposure.  There are 70 exposures, 112 GBytes and
some dark frames.  

My impressions is the the lens is much better than the camera lens I tried
before.  The camera lens peaked in the middle and was off by 50% at the
edges.  This lens is pretty flat.  There are some bumps but they are at the
few percent level.  So here is a project for someone.  Look at the data and
draw some conclusions about the quality of the optics.  

There is coma in the corners.  Looking at a corner star, it looks like a
little moth with its head pointing at the corner.  i.e a bright head
trailing off to the wing tips.  Again here is a project for someone.  Look
at the coma and see if it meets our expectations.  As I look at cross
sections of the "moth" it does seem that most of the energy is in the head
region.  

At the moment, all the data is in my raw format.  It is no problem to read
it into "Image Scientist", and I assume no problem to read it into any of
the utility astronomy programs.  There are 2054 pixels in a line and 2036
lines, and it is Intel format and the pixels are signed 16 bit integers.  

I will take orders for data for those that want to take on projects to look
at it.  Today would be nice, as I will erase the disk this evening as it
looks like another clear night.  After that I will have to copy from a
disk, and that takes longer (I think).

Even with the periodic drive problem, the data looks better thant he Mark
III data to me, and there is a lot more of it.  It is also simultaneous V,
I data.  Something not many people have.

Tom Droege