mark iv

[aah@nofs.navy.mil]

I mentioned to Tom many months ago that the best way to do
focus is with a 'focus plate'.  This is a single exposure with
multiple images, each taken with a sequential focus setting.
You can either physically move the telescope between exposures,
or you can do a partial read-out of the chip between exposures.
This is a much more convenient (and space saving) method of
finding the proper focus than taking a series of images.
  If you have a choice of fields for taking the CDROm exposures,
I'd pick either something along the equator or a series that
includes M67 (132.8, 11.8 degrees, or 8:51, +11:46 in sexadecimal).
Both the equator and M67 have good calibrations, so that we can
check your color transformations as well.
Arne