Re: [TASS] Flat fielding

[Tom Droege <droege@WWA.COM>]

Andrew,

It is worse than you can possibly imagine.  There is a gradient in the sky
and is changes from minute to minute.  Particularly in the red and near
infrared.  Something nice to study, I think.  It may be more than just
lights.  I still want to look for cosmic snow balls with a really wide
angle lens.  I don't think much work has been done on this.  A good library
project for starters.  That is what is nice about this project.  There are
so many things to try to look at.  I also want to take a stereo pair - a
couple Km apart.  Wide angle lenses.  Look for stuff whizzing by between us
and the moon.  I bet we would see things.

So get out your secred aganda and get going.

Tom

>Has anybody looked at night-night variations in flat
>vectors? Seasonal variations? One would expect the N
>edge to be darker (closer to the zenith) in the winter
>and possibly brighter (closer to the set sun) in the
>summer. Or either of the above if there is a bright
>cloud nearby.
>
>Needed: a dome flat technique for the Mk III.
>
>Andrew Bennett, Avondale Vineyard, Nova Scotia, Canada.
>
>