RE: V image fainter than I

[Richard Klappal <klappal@xnet.com>]

Speaking as a lurker, I'd change the V vs I parameters in the data reduction
process to accept the difference.  Don't throw out (or block) good data.

Richard

-----Original Message-----
From: owner-tass@listserv.wwa.com [mailto:owner-tass@listserv.wwa.com]On
Behalf Of droege@snapmail.us
Sent: Friday, 18 March, 2005 13:20
To: tass
Subject: V image fainter than I


As I am setting up the camera for the coming run I notice the V camera is
even fainter than usual from the I camera. I don't know why and have
changed out the camera.  We shall see if it is a camera problem when I get
some clear sky.  I have done all the obvious things like look through the
lens for dead bugs and hanging chad.

There has always been a bad match.  Many stars are lost because they are
too bright in the I images and others are too faint in the V.

Rob tells me that different exposure lengths are a pain.  The alternative
is to stop down the I camera.

The I filter has about twice the bandwidth of the V filter, further the
CCD is more sensitive in I.

At the moment, the I camera has a great focus.  I really hate to throw
away all those photons now that they pass through the optics so well.

Should I stop down the I lens?

Any comments?