It had been well reported that the first SXV guide
cameras did not have particularly good sensitivity. For a
page highlighting these issues see http://www.schmid-koenig.de/astro/instruments/sxvh9guider.htm
starlight has changed to using ICX405 CCD's in their latest
guiders to enhance sensitivity.
the data sheet these CCD's are very nice devices.
anyway, I bought the new guider, plugged it into my guide
scope and focused an a bright star. Then I entered a series
of M objects around Leo into ACP and asked for pictures of
all. In every case the imaging failed as Maxim could not
find a star to guide on. The problem was the camera was just
not sensitive enough.
The problem did not seem to
be the CCD as the recent Sony devices have a good
reputation. Other possibles were readout and thermal noise.
the guide camera was not going to be much use in an automated ACP
type set up I was either going to have to ask for a refund to try
to improve things.....
The next couple of pages describe
adding a cooler to the SXV guider and what happens when this is