Saturn April 3rd - Critique wanted!

[Poita (Peter)]

I got some colour video early this morning (about 3am) after wasting most of my hard disc space accidentally capturing my DBK as mono without realising it.

I didn't have long left when I realised, so this is a quick stack of my last minute effort. I think I can do better by handpicking the frames, so that is on tonight's to do list.

I'm not doing well with the wavelets, I'm going to try Paul's deconvolution method later today.
I have attached the stacked but not sharpened image as well if anyone wants to have a go and learn me up, it would be most appreciated. Any light that can be shone on the post-stacking process would be most welcome.
Actually, all comments welcomed, I have a skin that a hippo would envy so critique away.

EDIT: The upload converted the 16bit .PNG to be an 8bit .JPG, I have attached the 16bit file as a .zip

[Poita (Peter)]

Oh, I forgot to mention, it was with my C9.25, the older model DBK21 @ 30fps, stacked in AS!2 and had a go at wavelets in Registax 6.

[Quark (Trevor)]

Looks like reasonable data Peter, I have no experience with colour cameras, well other than my old ToUcam, so am not up with processing that sort of data. As far as limiting the number of frames to stack I think Emil's most excellent AutoStakkert 2 does a pretty good job, If you go that way you also need to run your data through Castrator first.

I would encourage you to record on paper everything you do everything you try with your processing and capture regimes. Experience is a great teacher, even trying things that don't work is a lesson learned.

Stick with it.
Regards
Trevor

[jjjnettie (Jeanette)]

Colour wise, there is a blue cast over the rings. I notice that I get the same. Desaturating the blue channel a little with fix that.
It's hard yards isn't it. So different from DSO work But enjoyable just the same.

[Poita (Peter)]

Thanks, for that. The whole thing looks a little blue doesn't it?
I just balanced the RGB channels during capture, I haven't attempted colour correction yet, I'm still looking for sources to base it on.
Any ideas?

[jjjnettie (Jeanette)]

As with DSO work, I find an image that I admire and try to emulate it to the extent that suits my own interpretation of the object.

Don't be afraid to experiment.

[lepton3 (Ivan)]

Peter,

Nice sentiment, but you can't effectively wavelet (or deconvolution for that matter) process an image that has been converted to jpg. You need to use the uncompressed 16-bit tiff.

FWIW, here's my flow.

1) Use Autostakkert! 2

2) Get a video with at least 3000 frames, 6000 frames is better. Castrate it so it is manageable.

3) Use lots of alignment points, big or small depending on the detail at that part of the image. You want to pretty much cover the object of interest. I will post an image of the APs for a recent Saturn session if requested.

4) Produce an output stack of between 900 and 1800 frames. 1800 frames will let you sharpen more. Use tiff output format. Normalize the level to a value which will give you headroom to work with:

Mars -- 65 to 75% (depends on how much cloud there is!)

Venus -- 55%

Saturn -- 75 %

5) Sharpen with wavelets in Registax 6, keeping an eye on the output histogram. Do not allow saturation (go back to stack and use a lower level if you are saturating). I like to sharpen too much, conventional wisdom is don't go too far.

6) Adjust colour balance LAST.

My 2c worth.

-Ivan

[Poita (Peter)]

Sorry, I thought I had uploaded the 16bit PNG.
I have fixed that now. I'd love to see a shot of the APs.

[Shiraz (Ray)]

hi Peter - re colour balance, there is a neat pugin for GIMP (assume it works in PS) called Grey Point - use the sampling tool on a part of the image and Grey Point will balance the colours so the sampled part of the image ends up neutral grey - getting the rings to grey is a good starting point for a sensible colour scheme. IRIS also has a similar function called White.

[lepton3 (Ivan)]

OK Peter, here are some screen shots of stacking and sharpening a Saturn AVI. I use a mono camera, so this is the L channel.

AS!2:

Bring it into R6 for wavelets:

The result (nice and sharp!):


I'll use the same stacking and sharpening settings for each of the R, G, B channels, but usually the L is treated differently as you take more L frames.

Combining them in gimp is another exercise.

-Ivan

[Poita (Peter)]

Thanks so much for sharing that info, I'll do some reprocessing tonight and see how I go.
I've shared links to this thread in the beginners section as well, it is valuable stuff!

[carlstronomy (Carl)]

Hi Peter, I ran your image the through my wavelet settings, see what you think.

Carl

[Troy]

Good image Peter 8-)