Brian Colville(300mm F10 Schmidt-Cass:CCD camera)
After a 6 week gap in imaging, I managed to get out for a few hours on the
evening of October 21 (Oct 22 UT).
Tha attached images were all taken with the 30cm Schmidt-Cass scope at
approx f24 and the Pixcel 237 CCD camera, operated in the medium res mode
(2x2 binning = 14u pixels). The RGB images were taken through SBIG CFW8
filters, and the times are based on the middle exposure through the green
filter. The IR passing filter is centred on 894nm, 337nm FWHM. The
methane band was imaged with a filter centered on 889nm, 18nm FWHM.
The RGB and IR images show a white spot approaching the preceeding limb
near the north edge of the NEB in the top row of images. The methane image
is somewhat later in this series and it shows this spot as well as another
in the NTeZ close to the limb. Oval BA and another are coming into view in
the methane image. A prominant dark spot is also visible in the IR image
along the north edge of the SEB.
The middle and bottom sequences show the transit of BA and the preceeding
white spot. There are also three dark spots along the SEB and a large dark
bar and dark spots in the south edge of the NEB. These dark features are
best seen in the IR images. There are also a few dark spots in the EB.
I have one image yet to process taken in the hi-res mode with the IR
filter. It should be out in the next day or two.
I have attached the hi-res image taken on Oct 22. This is an average of 10
x 0.5 sec exposures. Images were dark and flat calibrated, processed using
Maximum entropy, unsharp masked and finally a bit of brightness/contrast
This image used the same camera/scope (Pixcel 237 CCD/Meade 30cm SCT @ f33)
as the images sent out last night, but the camera was operated in unbinned
mode (7.4u pixels). This image was taken using the IR passing filter,
centered on 894nm, 337FWHM I believe that I stated that the f-ratio was
f24 on the note I sent wiht the image yesterday. It was actaully f33. In
this mode (hi-res) the camera is recording approx 0.15 arc sec/pixel and
0.3 arc sec/pixel in the 2x2x binned mode.
There are few nights that I can take advantage of the hi-res mode, but the
2x2 binned mode works well for the optical and atmospheric limits that I
[ Brian Colville : Cambray Canada]