Jupiter 26 October - reprocessed

[AstroFlyer (Arek)]

I have been trying different processing techniques with my best shot of Jupiter so far.(Original was posted here. First shot.)
Very subtle changes, but is it too much?
Am I introducing too much noise?
Meade LX90 8" +Televue 2.5X Powermate + DMK21Au4 + Celestron 1.25" UV IR Cut-Off Filter.
Also I seem to be getting an "onion ring" on the edges, esp. top left?
What causes that?
Thanks for any advice.
Cheers
Arek

[Quark (Trevor)]

Hi Arek, a creditable result, the partial ring is likely the result of over cooking the sharpening with your processing.

The classic onion ring ( which I would not call this) can be due to a number of things, too much gamma will do it as well as too little gain but the worst cases I have seen probably involved very heavy handed processing on pretty ordinary data.

As the image scale is increased any flaws obviously become more apparent. The tools that are available to amateurs now days are very powerful and it is easy to apply them to heavily in an attempt to extract just that bit more detail.

Looking at this image of yours I think it is just a little over sharpened and that is the cause of the ring artifact. You have listed the equipment used but not your processing regime, without knowing what you are applying to the image it is very hard to give advice, however this is a nice image.

Regards
Trevor

[Matt Wastell (Matt)]

Hi Arek - that is a great image!

[AstroFlyer (Arek)]

Thanks for the comments.
My processing regime was based on Paul Haese's article, using very similar settings.
Started with 1783 frames, processed in Registax5, final stack of about 900 frames, saved as TIFF. I have only adjusted wavelets 2 & 3 , approx. 13 & 22. No other adjustments in Regaistax.
The ring becomes visible even then.
I then used AstraImage 3, Lucy Richardson Deconvolution PSF size 0.7, iterations 3. Gamma adjusted down a fraction,minimal unsharp mask.
Photoshop CS5, canvas resize, evel adjust - middle slider moved to 0.95, samart sharpen - radius 9.8, 19% & saved for the web.

Is it possible that the ring is caused by misalignment of some frames?

Question regarding exposure:
Using IC capture I try to fill the histogram as much as possible. Usually set frame rate to 30, gamma to 100 & adjust gain to get nice histogram. In this case gain was around 875 from memory. Is this the best approach?
I've tried using high gain setting ( around 1000) as some people suggest, but end up with very grainy images.
Thank you again for great tips.

Regards
Arek

[Paul Haese]

Nice image but I think maybe it is a little over cooked. Don't get me wrong this is going well. Just ease up just a little on the sharpening and the ring will disappear. Don't worry too much everyone gets these from time to time. Glad the tutorial is useful for you.

[Quark (Trevor)]

Originally Posted by AstroFlyer

Thanks for the comments.
My processing regime was based on Paul Haese's article, using very similar settings.
Started with 1783 frames, processed in Registax5, final stack of about 900 frames, saved as TIFF. I have only adjusted wavelets 2 & 3 , approx. 13 & 22. No other adjustments in Regaistax.
The ring becomes visible even then.
I then used AstraImage 3, Lucy Richardson Deconvolution PSF size 0.7, iterations 3. Gamma adjusted down a fraction,minimal unsharp mask.
Photoshop CS5, canvas resize, evel adjust - middle slider moved to 0.95, samart sharpen - radius 9.8, 19% & saved for the web.

Is it possible that the ring is caused by misalignment of some frames?

Question regarding exposure:
Using IC capture I try to fill the histogram as much as possible. Usually set frame rate to 30, gamma to 100 & adjust gain to get nice histogram. In this case gain was around 875 from memory. Is this the best approach?
I've tried using high gain setting ( around 1000) as some people suggest, but end up with very grainy images.
Thank you again for great tips.

Regards
Arek

Hi Arek, prior to Registax try running your avi through either ninox or castrator. To use ninox you will have to run your avi through Virtual Dub to convert the avi to individual bmp files or you could just run the avi as is through Castrator. That will align all of the frames of the avi, then load the output avi from Castrator into Registax, I think you will find that Regi runs better as the frames will already be aligned.

Dont know how many frames you use to create a reference frame, I use 150, you really should put a lot of effort into making a very good reference frame.

I used to use a DMK but I cannot remember what the default gamma setting is, check this out and leave your gamma at the default setting for your camera.

With Astra Image I prefer ME decon, it is much more subtle than LR. I use ME more to reduce the noise rather than going for the more dramatic results that LR delivers. All of this is dependent on how good the data is. If the data is pretty ordinary then as a last resort I use LR.

Above all else have fun and enjoy the learning experience of planetary imaging, experiment and see what works and what doesnt work for you.

Regards
Trevor

[AstroFlyer (Arek)]

Thank you so much for all your great tips & advice.
I'm currently in image processing kindergarten so I need all the help I can get.
I've been using 50 frames to create a reference frame, will try 150.
Tried Castrator already - great!
I am definitely enjoying this - the more I learn the more I realise there is so much more to learn...
Very lucky to have this great forum to help kiddies like me.
Much appreciated.

Arek

[Rigel003 (Graeme)]

If you're in image processing kindergarten, you're rapidly moving to the top of the class - these are very good images.

I just did a Google search on "Castrator" and the results were painful.

[multiweb (Marc)]

Pfwoarhh! This is awesome! So sharp.

[AstroFlyer (Arek)]

Thanks, but I think it's a classic case of beginner's luck

Originally Posted by Rigel003

I just did a Google search on "Castrator" and the results were painful.

Yeah, how about search results in "Images"?
My eyes are still watery...