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Camelopardalis
22-01-2016, 11:06 PM
Folks,

We've had a couple of nights of half decent seeing this week before the weather reverts back to summer humidity and storms again :D

This is the first effort, having sifted through much of the data and having a messy stab at derotating...note the splodgy Ganymede in the top-left ;) I have some extra frames from before the transit started that I'll try and put up later.

Taken with my C11 EdgeHD / NEQ6 / ASI224MC from my square metre of scope space here in Brisbane.

As always, suggestions/recommendations for improvements welcomed - derotating is a tricky business :help:

Edit: added a second image from one of a short image sequences...no derotation but a little heavy handed wavelet application :screwy: Ganymede is a easier to discern as it's not smudged like in the derotated image, but the details are less clear and it looks...mmm...can't put my finger on it :shrug:

Edit2: added an image from slightly earlier before showing Ganymede on approach to transit and Callisto just sneaking behind. Not de-rotated, just stacked and waveletted.

Cheers,
Dunk

oernulfs
23-01-2016, 05:17 AM
I know little or nothing about derotation, but I know that so far I have not been able to reveal so many details as you have in your image (I have a C9,25). Nice work :)

Camelopardalis
23-01-2016, 01:12 PM
Thanks Ørnulf! You should give it a try and see if brings out any extra details :D

AstroJason
23-01-2016, 02:42 PM
Nice one mate, some great details there. Is this the first time you have used your new ASI224MC?

RobC
23-01-2016, 06:10 PM
A lot of detail there. How necessary is it to de rotate ?

Cheers

Rob

Camelopardalis
23-01-2016, 08:37 PM
Thanks Jason! Yeah it's the first time the 224 had been used in anger :D



With Jupiter you can eek out more detail if you derotate because it rotates so quickly that the details can suffer motion blur if you stack frames from a single capture sequence lasting more than a couple of minutes.

sharptrack2
25-01-2016, 02:23 PM
What is meant by de-rotating? Are you referring to the planet rotation or camera rotation?

I've decided I want to do solar system observing/photography and this has me a little confused.

Camelopardalis
25-01-2016, 11:51 PM
Derotating...check out WinJUPOS...it works some magic on your data to try and reverse the motion blur I described above.

Btw, this is the planet's rotation not the camera...the stacking software doesn't care about a little field rotation, in case you're using an alt-az mount.

sharptrack2
26-01-2016, 10:30 AM
Thank you Dunk,

Not quite ready to photograph yet but learned a long time ago to ask questions when they come up. Appreciate your reply.

Great images BTW!

andyc
26-01-2016, 06:23 PM
Nice shot Dunk! Love the bit of detail on Ganymede in the 2nd shot

Somnium
26-01-2016, 06:51 PM
getting some good detail there Dunk

Camelopardalis
26-01-2016, 11:06 PM
Thanks Kevin! Never fear asking questions :)



Thanks Andy! I was surprised about the Ganymede markings myself - pretty chuffed! I have some more sequences before Ganymede got so close, and with Callisto just playing peek-a-boo as it was occulted. I'll have to take a closer look and post 'em :D



Thanks Aidan! We are at the mercy of the seeing :D