Brian COLVILLE #237

Letters to the Editor


from Brian COLVILLE in CMO #237
@ . . . . 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 adjustment.
  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 2x2 binned mode. . . . .
(26 Oct 2000 email)

@ . . . . I have attached images from my three latest observing sessions, which have taken some time to process..

  29 Octber 2000

  04 November 2000

  07 November 2000
Click on the image for full size file  

  All were taken with the Pixcel 237 CCD and 30cm Schmidt-Cass operating at f34. A variety of filters were used, including IR, Methane, UV, and RGB. Details are noted on the images.
  Most images were taken in the medium resolution mode, binned 2x2, yielding 14.8u pixels. I had some luck imaging in hi-res mode (7.4u pixels) and the hi res images are attached as seperate files. Each IR image is the average of some 3 to 6 seperate images and the UV and Methane images were obtained by co-adding 5-6 seperate exposures. The IR images taken November 04 and 07 are among the most detailed I think I have ever obtained. Of interest is the November 7 image which shows a dark feature crossing the red spot, and the inset shows a contrast enhanced cropped image of the area around the red spot.
  Camera control and image calibration via Maxim CCD. Calibrated images were averaged and de-convolved using maximum entropy. These images were then unsharp masked and brightness/contrast adjusted. I welcome any questions or comments on these, especially the November 7 red spot image.

(12 Nov 2000 email)

Brian COLVILLE (Cambray, Ontario, Canada) : maple@quicklinks.on.ca
Maple Ridge Observatory
WWW : www.quicklinks.on.ca/~maple