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Startinez

Lunar Pic - Advice Wanted

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Posted (edited)

From Wednesday 10th April, it was my first chance of lunar video with my new Altair GPCAM3 224C.

 

Untracked through a f/10 90mm refractor, I managed to get a half decent video despite the breeze being quite a pain and I'm sure dropping the quality of the frames. I processed the original video of around 1.5 minutes using PIPP and used the Solar/Lunar close up options, then used AFB & AOI in processing options to crop to a 311 frame video, of which a still is below.

 

From here I stacked in Registax using (I think) 25% of the original frames, taking it to around 90-95 in total, and then I adjusted the wavelets to around 13/11/8/5/2/1.5 (approximation, really can't remember). This led to the below TIF being saved ready for editing in GIMP. After playing with the levels and curves and then finishing off with a slight brightness/contrast adjustment, I exported the below PNG which you can see has got some very annoying white spots on the upper left and lower right borders. I simply cropped these from the final image as I couldn't find another way to get rid of them without detrimentally altering the composition of the rest of the image.

 

This is basically the final image however I just cropped the white upper left & lower right areas. Any help or guidance much appreciated as despite being fairly happy with the amount of detail I can see, I know there's a lot more there to come from properly processed data.

 

Edit: I composed this thinking I could insert pics at various points. Apparently I don't know how to do that... so they're all wherever uploading them decides they will be ☺️

Still Frame - Video.PNG

0002_pipp.png

0002_pipp-final.png

0002_pipp.tif

Edited by Startinez

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Less is more? Don't be so aggressive with wavelets, you are aiming for natural feel rather than blowing all features up

image.png.45037914bed372db960b49f24e2ab1c2.png

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22 hours ago, vlaiv said:

Less is more? Don't be so aggressive with wavelets, you are aiming for natural feel rather than blowing all features up

image.png.45037914bed372db960b49f24e2ab1c2.png

I read a quick tutorial on how to use the wavelets feature as I didn't really know. So I've produced the image below, which I think is much more realistic. Thanks for the advice.

0002_pipp-final2.png

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Were the white strips only on the png?  I've seen something like that in gimp before when I exported to png and I was able to eliminate it by setting the compression level much lower than the default value of 9.  

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6 hours ago, DarkAntimatter said:

Were the white strips only on the png?  I've seen something like that in gimp before when I exported to png and I was able to eliminate it by setting the compression level much lower than the default value of 9.  

Those are due to wavelets edge artifacts. Wavelets work by decomposing signal into multiple subsets by use of particular filter (registax uses Gaussian). Such filters create edge artifacts because of "missing information" on the edges - no way of knowing what pixel values are "beyond" the image, and often value of 0 is assumed. This leads to sharp transition between area outside image and image pixels. Such sharp transition gets "sharpened" even more and this creates edge effects - often "ring" like - multiple white borders. Similar thing can happen on edge of planet being imaged if you over do wavelet sharpening.

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The second image with less aggressive wavelet sharpening is much better. So much depends on good seeing and getting enough raw frames that can be stacked. Good start and keep at it. All Astro imaging is about practice. The more you do the easier it will become but we all strive to get a better image next time and are never satisfied. 

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I agree with the above, be less aggressive with the wavelets.

My rule of thumb is the if you start with sliders 6 & 5 you can wind these up to 50% or more, after that 3 &4 then less with 1 & 2.

I alter the sliders in pairs and perform a 'Do all' between to see what the effect is and what noise is being introduced.

 

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