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After a few nice views of the sun today in the 4", I switched out the Herschel Wedge for the Zeiss prism, Barlow and Leica zoom to have a go at Mars and Saturn. I wasn't expecting much after such a hot day, but the reality was far better, some of my best views of these two this year. As ever, I'm a little uncertain of the mag because of the exact spacing with the Barlow, but I was probably maxing out at x180 or so, but possibly x200. Detail was visible even at much lower levels. Emphasising the beauty of this setup, I only had about 15 mins to observe, so I carried it down to the bottom of the garden where I get a clear view of the two planets, had some nice views, then just packed up quickly, all done in about 25 mins I should think. Anyway, on to the views. Mars immediately looked great, the seeing was good, and surprisingly steady. The phase was clear, Syrtis Major obvious, and defined well. I could see the north polar cap, getting obscured by the phase now. To the south, Hellas Planitia showed as a bright area, looking a little like a big polar cap but more orange than white. These views were unfiltered, the sky background was bright and Mars itself a pale orange colour. I popped the Mars B filter in and immediately the sky background was virtually black, giving Mars a nicer apparent contrast. Mars itself appeared a deeper orange colour, more Mars like if you will . Syrtis Major appeared darker and slightly better defined, but Hellas Planitia was dimmed and I lost the polar cap. The Mars B didn't show any more detail (based on this brief view), but I did enjoy the views as an alternative. I need to try the less aggressive Mars A filter which may be a better compromise. Should also give the Neodymium a go too which is very effective on Mars, but not Saturn for some reason. Note to self, probably should get a filter slide for my 1.25" filters to make comparisons easier, I have plenty of infocus range so it should work fine. One obvious statement is the importance of focus in picking out the detail. Very small tweaks on the fine focuser significantly improved the views so it's well worth getting it right, and using a dual speed focuser if you can. On to Saturn, and again the best and steadiest views I've had this year. The Cassini division was very clear other than the thin section infront of the planet where I lost it. It was visible most of the time, but became vague when the seeing dropped off every now and then. This was only a quick session so my recall of features is a bit hazy! A and B rings were clear. I believe I saw the Crepe ring in front of the planet, but need to verify again whether this was the case. The darker section in the B ring was visible, as was shading/banding on the surface. The only moon I could detect was Titan as it was still too bright for the others; I know that at least 5 are visible in this scope under good conditions. So, a long report on a short session. I'm mainly writing it because I don't seem to have had much luck with these two so far this year, either too low, poor seeing, cloud or too busy so these views were very welcome. It's often said (by me too!) that you need to spend a long time observing to pull out the detail in planets, well last night that was not the case, detail was clear right from the start. I could have spent an hour on them, but Mrs Stu was ready to turn in, and I know better than to disobey the CEO . The images attached are approximations of what I saw, or at least they are on my iPhone. The main difference with Mars is that I could see the polar cap (in the unfiltered view) which has been lost in this image which is more similar to the filtered view. Saturn is shown against a brighter background as it was unfiltered. They may be too large a scale on a full screen, so don't look too closely . Just trying to give a rough idea without having done a sketch.
I can't believe how long it is since I have been out with my 'scope! This is a quick process of 1000 frames using the best 5% processed in AS2! and then tweaked in PS CS4. Scope: Celestron C9.25 Mount: Celestron CGEM Camera: QHY5LII colour