I was lucky enough to have some really good seeing to observe Jupiter last night. I knew the GRS was making an appearance around 10pm so I set up the C8 and Tal100RS side by side on the Skytee II a couple of hours early to allow good cooling time. Come 10pm I had my first peek at the giant through the C8 and was amazed at the detail. The GRS was easily visible on the eastern limb and lots of detail coming and going. I decided to get my book to make notes and do a little sketching so i wouldn't forget.
What I saw
Through the C8 the southern and northern equatorial belts were clearly brown in colour, the northern belt being slightly darker and more prominent, and the southern belt having a very faint white line running along the middle of its length. A further belt was visible toward each pole with the north polar region showing as a darkening. The GRS was a bright amber or rusty orange in colour, very prominent and colourful, embedded in the southern half of the south equatorial belt and apparently separated from it by a gap. The northern equatorial belt showed two prominent dark areas which were grey in colour, one of which was near the GRS and had a long 'arm' which protruded into the white equatorial band. There was lots of fine detail coming and going, particularly in the northern equatorial belt. Try as I might I could not see any white spots - are they visible visually in a C8? After an hour the GRS had moved considerably and my sketch was out of kilter - note for future, make sketches quicker!
The scopes
I found that 200x was the best magnification with the C8 and my limited set of eyepieces. I cranked it up to 400x but nothing more was visible. I suspect more than 250x would have been doable with a decent eyepiece. I had a go with the Tal at 200x and was pleasantly surprised at the detail visible. The image was significantly dimmer and I was finding floaters were interfering with the fine detail, but if this was my only scope, I would have had plenty to look at and been very happy with what I saw. CA was not really an issue. Surprisingly the Tal dewed up much quicker than the C8. The scopes were dripping after an hour so I put the dew heater on the C8 for stress free viewing.
Filters
I tried a few filters in both scopes in the hope of revealing some additional detail, possibly some white spots? I tried a yellow, blue, green and orange filters (wrattens 12, 80A, 56 and 21). The yellow gave the the most pleasing view, probably because it was brightest, but no additional detail was visible in any if them. I would have persevered but the natural colours of the planet were so nice that I returned to filterless viewing.
Summary
I spent a good hour and a half observing and had a great time. The conditions came together with good seeing, a scope which behaved itself perfectly and Jupiter showing itself at its best. My biro 'sketch' was not really something to share, but was a good way to record and remember what I saw.
Might have another go tonight!
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