great night last night(20/06) with the new EQ6 and mounted 8" SW dob.
Polar alignment was better than last attempt. 3Star alignment was roughly 3-4degrees off on each target; and afterwards an object in view drifted slightly every ~10mins.
Joop being next to the moon intially was too blurry to see up close as they both rose behind the tree at about 40-50dgre above my horizon.I spent the time viewing the Messiers in Scorp; and getting use to the different rates of speed when slewing and marveling over the EQmounts operation.
Sounds made by the motor (the pulsing) sometimes had me concerned when it would whine at certain points, with making minor key presses when slewing at certain speed rates.
Then after an hour or so; I thought Id slew back to Jupiter before I slewed to the moon to try and spot the expedition teams activities building the 4km lunar post array
My gosh! Jupiter was so clear; the wind had gone calm from 7-8knots and I could see the storm bands and textures on Jupiter! Using the 3x barlow and 17mm plossl; for an hour or more I could see bands of cloud, and texture I've not seen yet. Bewilderment took over as I could see a circle indent on the darker lower band near the front edge of Jupiter. Over 30mins-1hr, It moved along the dark band?! Can you see the dark spot or a dark spot move along the storm band during the hour ? I needed another viewer to confirm what I was seeing. The rush of discovery, awe and excitement.
I tried to push the viewing further with the 10mm plossl; but it underperformed and was too blurry to see; though I could just make out the same detail. I need something better; perhaps a Nagler is what I need.
What may have been illusion of light or my eyes is Io seemed to be shining a distinct yellow compared to the other moons ?
Hoping the conditions tonight will be ok; so I can setup again.
Re the dark spot, there was an Io shadow transit yesterday evening so this may be what you were looking at. Check Sky & Telescope's on-line predictor or download predictive freeware such as Jupiter 2 (just Google it). 
