My recent first light experience using the large format Dream Machine
camera showed serious vignetting with the C14.
I used an Optec TCF-S focuser attached directly to the back of the
scope, followed by a Celestron F6.3 reducer/corrector which screwed
directly onto the shutter housing of the DM.
The vignetting was pretty horrible and really shows up in the Comet
Ikeya-Zhang image:
I tried the setup last night with no focal reducer and still got
pretty bad vignetting, which showed up in my flats. Unfortunately the
clouds covered things up before I was able to really get any images.
I am planning to remove the OPTEC focuser to get the camera closer to
the back of the scope for the next outing.
Does anyone here have experience using the large format ccd chips
with a c14? I'd be interested in your experiences regarding the
vignetting.
rdc
