Processing tips - separating stars ** Tutorial Uploaded **

[multiweb (Marc)]

Originally Posted by SkyViking

When adding the stars back in, try adding them as a separate layer on top of the nebula and setting the star layer's blend mode to 'Lighten'. That way only the portion of the layer that is lighter than the underlying layer is added in. Before doing that you can try sharpening the stars, and/or adjusting levels & curves for them if you think they don't quite fit the appearance of the stretched nebula.

Great thread by the way Marc! Thanks for sharing

You beat me to it.
What he said.

Thanks.

[troypiggo (Troy)]

D'oh. Shoulda thought of that. Obvious but didn't occur to me. Thanks guys!

Still some remnants of stars in my shot after the dust n scratches removal. Just need to finesse that out now.

[multiweb (Marc)]

Originally Posted by troypiggo

D'oh. Shoulda thought of that. Obvious but didn't occur to me. Thanks guys!

Still some remnants of stars in my shot after the dust n scratches removal. Just need to finesse that out now.

There are always abit of left over stars yes. The only person who can remove them all that I know of would be Fred. But I reckon it's beyond processing skills. He hates them so much they just fade away

[troypiggo (Troy)]

I've written what I think is a nifty little PS action that puts the stars back onto a starless layer. I think it's cool, but maybe everyone has already done this and it's nothing new.

So I've got an action that removes stars, I have a bit of a methodology to tidy up the starless image that seemed to work on my test image (not sure if it's practical to be in the star removal action), and now an action to add the stars back as a separate layer so they can be turned on and off. It's all coming together for me. I haven't reverse-engineered the AstroAnarchy way of adding and removing stars, so I don't know if my methodology is similar or different, but it seems to work and I think his actions need a bit of work as sometimes they fall over if your layer naming isn't quite right. (Actually I might email him with fixes for that. )

When I get a chance I'll put it all together in a bit of a tutorial with downloads and screenshots etc.

[gregbradley]

Hey Troy.

That sounds useful.

Do have a place to download the action?

Greg.

[troypiggo (Troy)]

This might be a bit premature, but would be handy to get some feedback. All of the actions should be non-destructive (ie they create and work on copies of the current layer only).

I use the threshold crop one to trim off alignment/stacking rubbish around the outside of images first thing after bringing into PS from Nebulosity. Tried to include a dialogue box to explain usage.

Big stretch and small stretch are just some curve adjustments to bring out some detail. I use big stretch typically first, maybe a couple of times, then small stretch sometimes helps but often don't and just use manual curves. Feedback on better curves appreciated.

Remove stars does still leave some artifacts that need cloning out manually. I'm working on a methodology of getting rid of those. Still not happy at this stage.

Star selection is probably a misnomer. Just put a duplicate of the original image with stars on top of your starless image, making sure there isn't any visible layers between them. Run the action and you can blink the stars/no stars versions by turning that top layer off.

Feedback appreciated.

Troy's Astro Actions v0.9.1

[multiweb (Marc)]

That sounds great Troy! Will have to try it.

[troypiggo (Troy)]

This is fun. Just updated the link above to version 0.9.1. Now included one action that separates the stars and the background with one click. Also made the action names a little more obvious.

[Andy01 (Andy)]

Hi guys, found this very interesting old thread and wanted to see if there were any other updates for this? I have downloaded Troys astro actions, thanks Troy, but Marc's links don't seem to work anymore?

Anyone else got a star removal action/tips to add?

Cheers
Andy

[coldlegs (Stephen)]

Originally Posted by Andy01

Hi guys, found this very interesting old thread and wanted to see if there were any other updates for this? I have downloaded Troys astro actions, thanks Troy, but Marc's links don't seem to work anymore?

Anyone else got a star removal action/tips to add?

Cheers
Andy

+1 for me too

Cheers
Stephen

[multiweb (Marc)]

Originally Posted by multiweb

Here's a link to the procedure I used as a few people showed some interest. This should give you a base to start from and an idea of the processing flow. Feel free to add your own stuff and experiment. That's what it's all about.

Just saw this now. Updated link above. Troy should have a link to the action somewhere.

PS: found it. See attached zip file.