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Posts Made By: Roland Christen

May 12, 2005 04:56 PM Forum: Bad to the Bone Autos

May 17, 2005 07:50 PM Forum: CCD Imaging and Processing/Deep Sky

Leo Trio galaxies

Posted By Roland Christen

Wide field shot taken with my AP105 F6 Traveler, detail in the galaxies added with the AP230mm F4.3 FastMax.

Roland Christen

June 2, 2005 01:29 PM Forum: CCD Imaging and Processing/Solar System

Re: A Blue Jupiter

Posted By Roland Christen

The image seems to have a higher than normal resolution. Some have mentioned that it is incredible considering the filter used. I believe it is because of the filter used. People should realize that at 400nm violet, the resolution of any telescope will be 39% greater than at 555nm green. That would make your 9.25" aperture equivalent to a 13" instrument. Add to that the largish central obstruction of the C9.25, which increases the resolution slightly more at the highest frequencies, and your scope might be working at almost 14" effective aperture.

Roland Christen

June 3, 2005 08:56 AM Forum: CCD Imaging and Processing/Solar System

Last year's Venus Transit

Posted By Roland Christen

This image was taken in France. Details:
June 08th 2004. AP Stowoway F/5, with 60mm double stacked Coronado, and ST10 XME camera. 0.3 sec exposure, black and white.
Image taken by Franck Valbousquet.

Processed using MaximDL, and Photoshop by Gilles Cohen.

June 16, 2005 06:16 PM Forum: CCD Imaging and Processing/Deep Sky

M63 from French Riviera

Posted By Roland Christen

The image was taken by Gilles Cohen using the SBIG ST2000C one shot color camera in a heavily light polluted area of southern France. 20 exposures of 5 minutes each, 155 EDF refractor mounted on a 900 mount, processed in Photoshop.

Frankly, I'm surprised that a one shot color camera can do this well.

Roland Christen

July 29, 2005 02:48 PM Forum: CCD Imaging and Processing/Deep Sky

Veil last night in color

Posted By Roland Christen

Color image of the Veil shot through clear skies for once, but hampered somewhat by local light pollution from big box stores.

RGB 2x10 minutes each color, shot with 160EDF operating at F5.8 with ST10XE camera, 900 mount.

Roland Christen

July 29, 2005 05:26 PM Forum: CCD Imaging and Processing/Deep Sky

M13 wide field deep sky

Posted By Roland Christen

Well, as deep as I could go considering the amount of local light illuminating the sky.

Roland Christen

August 20, 2005 09:10 AM Forum: CCD Imaging and Processing/Solar System

Re: Mars on August 17th

Posted By Roland Christen

Dang, that's good! What's going to happen when Mars is twice this big? Will I need to get a 32" monitor? Mindblowing!


September 14, 2005 12:24 PM Forum: CCD Imaging and Processing/Solar System

Mars with ST10

Posted By Roland Christen

Taken night of Sept 10 with ST10 CCD camera and my 10" Mak-Cass at F30. The result is not as good as those taken with the better video cameras, but my first effort this season. Had only 50 images of Red and Blue and 100 of Lum, and Green for stacking. I'll probably try again tonight if it stays clear.


September 20, 2005 02:57 PM Forum: CCD Imaging and Processing/Deep Sky

Double cluster with 160EDF and ST11000

Posted By Roland Christen

This image of the Double Cluster was taken with my 160EDF refractor and an experimental telecompressor/corrector at F5.8. The attached image is reduced to approximately 1/4 of the original size of the ST11000 format. At that reduction, the stars became so tiny, that most of them disappeared on my computer screen. Therefore I had to try some techniques to get them to re-appear on the screen.

Normally one tries to get the tightest focus possible to get the prettiest picture, but in this case I actually had to defocus the image in Photoshop by applying a Gaussian blur to give the stars a bit of size so they would re-appear on the screen. On the original image, the stars had a FWHM size of 1.3 pixels, so theoretically when reduced down, they would have only 1/3 pixel size. This essentially means that they not only lose their size, but also most of their brightness when reduced. By blurring them, and boosting their brightness to the original levels, then reducing the image size, I was able to keep the colorful stars on the monitor.

This ST11000 is on loan to me from Ray Gralack for testing. I can see that it is extreme overkill for a typical computer monitor, but you should see what a 20" print looks like with full resolution. You have to examine it with a magnifier to see all the detail. I really like this camera, and have to think hard about whether I want to replace my trusty ST10XE. I thought that the ST11000 with its anti-blooming feature would be super slow to record stuff. I was basically wrong about that. This image consists of two 5 second exposures each of LRGB taken last night during a full Moon and somewhat hazy skies. Essentially a 10 second unguided image under poor conditions. Not bad at all.

Roland Christen