First ever Jupiter (& some newbie Qs!)

[vineyard]

Hello,

Having jumped up to a 180mm f10 MakCass from a fellow SGLer, I thought I would try Jupiter imaging for the first time last night.  ASI294MCPro (uncooled - yes its my DSO camera but I wanted a large FOV in case I had trouble finding the planet on the laptop 😂)

Its embarrassingly poor compared to the other images here, but hey ho got to start somewhere.

Some newbie Qs please (apologies mods if this is better in a separate section):

1.  I could only see it on the laptop when binning 2x2.  The screen would garble when Bin 1x1 - is that just my laptop (v old)?  I'd have thought the larger pixel sizes of the 294MCP were well suited for f10 but maybe that's just DSO?  Or is binning better on planets?

2.  I used FireCapture to capture, and then AS!3 to stack & then ImPPG & GIMP.  On AS!3 the image shows up in colour, but the .tif file that ImPPG opens is monochrome?  (I've tried auto-detect and force RGGB on the AS!3 options)

3.  Is that a moon on the edge of the disk (between 9 & 10 o'clock on the planet as you look at it on the screen)?

Cheers,

Vin

[vineyard]

Silly me, a little bit of googling answered some of the Qs.  For future reference for any other newbies like me: AS3 still generates a colour TIF, but ImPPG handles it as monochrome.  So what I did was open the AS3 output TIF in GIMP, decompose it into RGB channels, and then run each channel through ImPPG.  Then reopen each channel and recompose in GIMP.

Still not sure about the binning but on further googling, astronomy.tools shows that that combination is over-sampled, and becomes better at 2x2.

 

[Laurieast]

1 hour ago, vineyard said:

 

3.  Is that a moon on the edge of the disk (between 9 & 10 o'clock on the planet as you look at it on the screen)?

Have a look at the observation report by Nik271, "Excellent planetary seeing conditions!" refering to a dark spot. In Observing Planetary.

Edited September 22, 2021 by Laurieast

[vineyard]

Thanks - that's a good report.  I think the dark spot he refers to is within the planet itself?

I then found this helpful site: https://skyandtelescope.org/wp-content/plugins/observing-tools/jupiter_moons/jupiter.html & put in the observation time & indeed it shows as Europa coming out just at that spot on the disk at exactly that time 

Serendipitous!

Cheers

[Laurieast]

Or you can use JupSat in windows DOS  😉

 

[Nik271]

Europa was expected to emerge from behind Jupiter at 1:20am last night, so that must be it.

You should not bin for planetary imaging. Binning helps with noise for DSO but planets are fairly bright so you need the maximum resolition available from your sensor.

When stacking the usual considerations about star sizes dominating the choice of pixel scale not longer apply. Instead it's the focal ratio of the telescope which dictates what pixel size you need. I use the rule that for planetary imaging the focal ratio should be 4 or 5 times the pixel size in micrometers. At F10 this means that your pixels should be about 2 micrometers, i.e. much smaller than in your camera. 

I've never seen a F10 Mak Cass, they tend to be F/12 or F/15, even F/20. With F10 there should be a big central obstruction which kind of defeats the purpose of a Mak.   

[vineyard]

@Laurieast I'm a Mac person I'm afraid  Windows confuses me

Thanks @Nik271 that is really helpful - ah ok, I have a smaller pixel mono camera that I normally use for lunar & solar - will try that tonight!  Let's hope the conditions are as good 🤞🏾(the Mak Cass is an old Russian STF Mirage 7 that another SGLer was selling - am v-e-r-y happy with it for lunar & double-stars so far, & visual planetary.  Its a 64mm obstruction so more or less the same % as a Mewlon 180 but since I've never used another MakCass I can't really compare on a first-hand basis 😂)

Cheers!

[Pete Presland]

Very nice 1st image, some lovely details visible there.

[vineyard]

Thanks Pete, that's v kind.  Lots of rookie errors but those have to be made if one is going to learn anything   I was still quite amazed at what popped up on the screen.  Am keen to try again but with a smaller pixel mono camera, but having FW problems.  Ah well.  I can see how getting good planetary footage could be quite addictive - luckily for me there's only about an 1hr window of when Jupiter is visible so throw Bortle 8 on top of that w clouds, and I'm not sure I'll get that many chances to become an addict: many times I'm just quite happy to look at it visually!

[Clavius D]

Use Registax to sharpen the image after stacking with Autostakkert 

[vineyard]

On 25/09/2021 at 13:53, Clavius D said:

Use Registax to sharpen the image after stacking with Autostakkert 

I never got the hang of Registax unfortunately - have found ImPPG to be much more user friendly!

[happy-kat]

That's lovely to have caught a moon shadow, when you think about what that is it's amazing.

When I view this on a mobile phone Jupiter has a grid pattern like it hasn't debayered correctly.

 

[vineyard]

20 hours ago, happy-kat said:

That's lovely to have caught a moon shadow, when you think about what that is it's amazing.

When I view this on a mobile phone Jupiter has a grid pattern like it hasn't debayered correctly.

 

Yes it's quite something. @Pete Presland caught a lovely capture of I think the same transition (much better though!).

I suspect the grid pattern may be from my foolishness in binning it 2x2 so ruining the resolution - rookie mistake!

Edited September 27, 2021 by vineyard

[kirkster501]

Super image. Like you, I am learning this too. It is very different from DSO.  Some of the planetary images on here are incredible, like being in orbit.

[vineyard]

Thanks @kirkster501 - yes when I look at the images posted 😮

Agreed re so many different things and a new learning curve.  Its fun.  I'm starting to understand how & why gain settings depend on the image being taken (fast vs long).  Also the whole idea of IR-pass filters b/c seeing is less volatile in IR.  Fascinating stuff.

Haven't got to derotation yet - will leave that until I'm happy with the actual captures I'm grabbing!

And as always the expertise & openness of SGLers is wonderful to learn from just by being a fly on the wall (particular shoutouts to @vlaiv & @Nik271 for various pieces of advice they have posted, although that is not to exclude others!)

Cheers - looking fwd to seeing your images!

[orion25]

HI, vineyard. Thanks for sharing your image! Planetary imaging is a unique sport and you'll learn lots along the way. Don't be afraid to ask questions or to experiment! There's much experience and helpful guidance available here, as well as some cracking images! Enjoy!

Regards, Reggie🚀

Edited October 2, 2021 by orion25