I couldn't resist posting this image into its own thread... the seeing around 6am this morning was just fantastic, as you can see from the result!
This was with Jupiter at an altitude of 40 degrees, and I was only using about 10m focal length instead of the normal 14m that I prefer to use on Jupiter (I have been using 10m on saturn and decided not to change it over).
From now on I'll be going back to the 14m focal length for sure...
Capture: 60 seconds in each channel, R@40fps, G@50fps, B@35fps
camera: PGR Dragonfly2 mono firewire
What a ripper, Anthony. I'm glad you've been able to take full advantage of these clear and steady skies the last week or so. Your account is well and truly in the black.
As we said on email, if you can get this sort of image at 45deg altitude, it bodes well for Jupiter apparitions in a few years time when that's the maximum altitude we'll get.
If there was a Jupiter event at the Beijing Olympics - this image would win gold! You're really optimising everything under your control to reveal so much fine detail.
Thanks Mike, I also have data from an hour earlier that I'll try and work up into a decent image... after reading Johns report I think he could use an image showing oval BA & "LRS" a bit closer to the cm - do you have any data from around 1800Z (5am) ?
Yep, watching the seeing closely - this is our first year living out here and so I'm not sure when the best seeing is to be had. I've been surprised by a few of the mornings so far - great seeing right up to sunrise, and mist sitting around in all the valleys, not a breath of wind anywhere... I hope it continues!
I just remember from previous discussions we've had that late autumn and early winter seem to be particularly good around that region.
yep, they sure were, that was around April I think (from memory), still about a month away... Fngers crossed that means the seeing will stay good for the next few months.
With Jupiter moving 1 month every year it wasn't really possible to get any images in February last year, Jupiter was just too low. Even the early March images were poor due to low altitude so it wasn't really possible to test the seeing.
While waiting for the Good Seeing I'm going through data from last year, here's an image that was never processed, it's been sitting on my hard disk since June 22 last year :-)
This is probably the best image of Jupiter I've ever managed, and I have fingers crossed to get more seeing like this when J is at the zenith starting in April...
Wow Anthony – it’s so difficult trying to keep up with all these superb Jupiter images and then somehow find the brain space compare them to previous efforts, but boy oh boy, this one certainly looks tops!
Here's a copy of an email I sent to a colleague who lives about 15 minutes away. He was also up and observing jupiter this morning but found the view to be disappointing when he was looking (at about 5am). This was my reply:
"Jack, this morning the seeing was awful until about 5.30am, and then it improved steadily until it was quite good around 6.15am.
Bear in mind I only look at Jupiter in these sessions, part of the "seeing" that I find is related to it's altitude and relative location. I don't know what it was like elsewhere in the sky.
I nearly packed it in at 5am, the seeing was really poor. This can be predicted if you look at last nights temperature profile - it was unusually warm early in the evening, still 23C at 9pm when it should have been down to about 15C. Something was preventing the heat from escaping, I guess an inversion or some other impedance boundary was present in the lower atmosphere that trapped a lot of warm air and prevented the ground from radiative cooling.
Whenever this happens you can be sure the seeing will be appalling - both during the warm period when there is a nasty boundary layer present above you somewhere and also when this layer breaks and the heat starts escaping normally again you will get lots of convective turbulence in the air, also kills the seeing.
BOM was predicting an overnight low of 13C which was looking unlikely when I was still reading 20C at 10pm last night, but I took a gamble that the inversion would break sometime and the air temp would eventually equalise to the predicted value, so I set the scope cooling for 10C and went to sleep with the alarm set for 4am.
Well, at 4am the inversion was gone and the air was cooling rapidly, with the associated awful seeing that comes along. Luckily my guess was right, and by about 5.45am the air temp was down to 12C, and my mirror had slowly thawed from 10C up to 12C after I turned the cooling off at 4am. The turbulence abated and I got some reasonably nice images of Jupiter from 5.45 to 6.30 showing this mornings GRS transit. "
