Apr 132010


finally some decent seeing. Skies have been clear on the evening of April 10th so I set up the already cooled C11 at dusk. Contrary to the forecast the seeing looked quite good this time during collimation of the scope and some quick glances at Mars. Just after I fired up the laptop and camera clouds rolled in and obscured the only 8.5″ measuring Mars. Waiting a while was rewarded by clear views again. The session was interrupted several times by clouds but later the skies stayed finally clear. I started to image Mars with a 2.5x Powermate delivering true f/25 with the C11 and tried the Meade #140 2x barlow later delivering a longer effective focal length (!) than the Powermate behind the motor-focusser and filterwheel since it’s not telecentric like the Powermate.
Processing the first set of RGB captures shows that my estimation of the seeing was quite right, results are better than those of April 6th, no artefacts beside the diffraction artefacts at the bright limb.
I slewed over to Saturn after imaging Mars but some preliminary results aren’t on par at all with the Mars material. Maybe seeing degraded (again), maybe the lower altitude of Saturn was quite critical this evening. The main benefit for the Mars captures compared to Saturn should have been the much shorter integration times freezing the seeing. The Mars AVIs show only a single very good frame surrounded by much more blurred ones from time to time.
Here the first Mars result, not too shabby for 8.5″. More to come…

Mars 2010.04.10.

Cheers, Oliver