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View Full Version here: : A petite Jupiter animation: “Bird Strike”, GRS, Ganymede, Europa and shadow.


Dennis
23-07-2009, 04:53 PM
Well, what a night that was! The invisible column of air towering over my head connecting me to outer space, its base tethered in my back garden, had scant regard for my need to record the scars from the fresh impact site on the gas giant Jupiter. The planetary disc was literally boiling in the jet stream as the Wesley “Bird Strike” came into view at the Jovian limb (west). After a couple of hours, I capitulated; the Jovian disc was washed out, hopelessly smeared by the unstable jet stream howling along some 10-16 kms above, with fine wisps of cloud dimming this incredible sight.

But, a glimmer of light! In the end, I managed to record some 90 minutes of activity through removing my colour CCD camera, replacing it with the more sensitive mono version. In this animation, we can see (in the east) the Great Red Spot, Ganymede “leaving” the face of Jupiter stage right and Europa entering left (west), as it approaches the disc to cast its shadow on Jupiter, with the fresh impact site continuing to march across the lower limb (south).

Takahashi Mewlon 180 F12 with Vixen x2 Barlow and Imaging Source DMK21AF04 CCD camera.

Brisbane, QLD, Australia.
22nd July, 2009.
21:49 to 23:58pm AEST (UT+10)

WARNING: 640KB file
Animation: 90 mins here (http://www.iceinspace.com.au/uploads/Dennis-Jupiter-Impact-GRS-Gany-Europa-Crop.gif).

Cheers

Dennis

PS – I was left wondering, how many casual Jovian observers would be able to spot the difference between the shadow cast by one of the Galilean moons and a new impact site?

PPS - Thanks for the uploads Mike, you've been a busy fellow and I appreciate your help!

Quark
23-07-2009, 05:02 PM
Very nice job Dennis, well defined structure and detail.

I think that less magnification is the go when the seeing is crook, this animation presents all of the detail of current significance on Jupiter regardless of the image scale. A most pleasing result.

Regards
Trevor

bird
23-07-2009, 05:08 PM
That's extremely good Dennis, nice to see. I'm still stuck in rain and cloud...

cheers, Bird

allan gould
23-07-2009, 08:02 PM
Really, really nice Dennis. You really overcme the conditions to get a great series of shots.
Allan

Dennis
23-07-2009, 08:24 PM
Thanks Trevor, Anthony and Allan!:)

I almost downsized even further, contemplating removing the x2 Vixen Barlow and recording at the F12 prime focus (2160mm) on the Mewlon 180! I think the relatively small aperture of the ‘scope helped? I estimated the seeing to be approx 2-3/10 until around 10:30pm and then it recovered, in parts of some AVI’s, to maybe 4/10 and there was just enough there for Registax to do its magnificent work – what a killer application!:thumbsup:

As the seeing was so variable, I decided there was nothing to be gained by recording at Gain=975, 60fps and 1/180 sec exposure, so I dropped the Gain to 700, 60fps and 1/60 sec. The tactic here was to get “denser” and “richer” data at a lower Gain of 700 and hopefully, be able to stack sufficient frames to get a reasonable output from Registax.

I had to manually sift through each AVI the next morning, to assess if there were sufficient quality frames to make it worth processing; a really tiresome task! From those selected AVI’s, I was able to harvest between 150 and 450 frames from 3000 recorded, to generate the final TIFs. The Quality setting was varied between 96-98% to reject the shockingly bad lava lamp frames. Each final stacked TIF had Wavelet6=100, W5=75 and W4=50 applied.

I then (a first for me) applied a Maximum Entropy Deconvolution in Astra Image Pro 3. The settings were 1.4 with 5 iterations and this added a much needed punch to most of the frames and for the 1st time, the project began to look like a real goer!:)

Finally, I used a script to import the 30 files into Layers in CS3 and did a “File save for web and devices” to produce the final gif. My head freaks out at what Bird is having to do with his huge data sets, with the x3 up sampling and 24 hour process time!!!:eyepop:

Cheers

Dennis

davidpretorius
23-07-2009, 09:18 PM
Lovely images Dennis,

you have capture the Bird Poop well

Miaplacidus
24-07-2009, 06:34 AM
Very nice, Dennis.
(I'm fuzzed out here by poor seeing at the moment, so this is a much appreciated consolation for getting up early.)
Cheers,
Brian.

Dennis
24-07-2009, 03:29 PM
Hello,

Thank you for all your nice remarks – it has certainly been an exciting few days with Anthony’s discovery of the “Bird Strike”. :)

I thought that I would include a couple of examples of single, raw frames from some of the 3000 frame AVI’s captured early in the session (9:47pm) when the seeing was around 2-3/10 and one from mid-session (11:03pm) when I estimated it to get up to 4/10 for brief segments of the AVI.

Cheers

Dennis

allan gould
24-07-2009, 03:34 PM
Thats very informative, Dennis. Thanks for posting as I must admit these looks exactly like my single frames. Its amazing what Registax etc can pull out of the muck.

erick
24-07-2009, 04:18 PM
Super animation, Dennis! Thanks. :)