dust bunnies

Questions and answers about processing in StarTools and how to accomplish certain tasks.
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Mitch44
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Joined: Fri Oct 12, 2012 4:10 pm

dust bunnies

Post by Mitch44 »

168P Comet-001L.jpg
168P Comet-001L.jpg (247.7 KiB) Viewed 10646 times
Is there a simple way to remove dust bunnies from a Luminance frame without flats?
:?
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admin
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Re: dust bunnies

Post by admin »

Simple? No. Possible? Absolutely :)
The new Heal module in 1.3 was partly designed for this task.

What you will want to do is put the the bunny in a mask.

Then run the Heal module and set the 'New must be darker than' value to a percentage that approach the brightness of background level (it may be a little bit higher). You can do this by eye. I.e. if the mean background level brightness is about 10% of full intensity (white) then set it to 15% or so.

You'll see the Heal module fill in a plausible background. The 'New must be darker than' value is simply there to make sure it is not adding 'plausible' stars as well. If you see it do that, just lower the value.

Once you're happy with the 'plausible' background, it's time to add back in any stars that were healed out. For this, launch the 'Layer' module, click Undo->Fg and set the 'Layer Mode' to 'Lighten'.

Congratulations! You have now a a dust bunnyless image;
mitch_bunny_ST.jpg
mitch_bunny_ST.jpg (53.85 KiB) Viewed 10641 times
Hope this helps
Ivo Jager
StarTools creator and astronomy enthusiast
Mitch44
Posts: 3
Joined: Fri Oct 12, 2012 4:10 pm

Re: Masking Q?

Post by Mitch44 »

Why is it that when im done with Mask, the button keep flashing green , and ClEaR, Cancel, Keep, does not not shut it off. its like its telling me something is not finished..;;;any ideas.
Mitch44
Posts: 3
Joined: Fri Oct 12, 2012 4:10 pm

Re: dust bunnies

Post by Mitch44 »

Thank you this will help a lot once i get the hang of it...Mitch

admin wrote:Simple? No. Possible? Absolutely :)
The new Heal module in 1.3 was partly designed for this task.

What you will want to do is put the the bunny in a mask.

Then run the Heal module and set the 'New must be darker than' value to a percentage that approach the brightness of background level (it may be a little bit higher). You can do this by eye. I.e. if the mean background level brightness is about 10% of full intensity (white) then set it to 15% or so.

You'll see the Heal module fill in a plausible background. The 'New must be darker than' value is simply there to make sure it is not adding 'plausible' stars as well. If you see it do that, just lower the value.

Once you're happy with the 'plausible' background, it's time to add back in any stars that were healed out. For this, launch the 'Layer' module, click Undo->Fg and set the 'Layer Mode' to 'Lighten'.

Congratulations! You have now a a dust bunnyless image;
mitch_bunny_ST.jpg
Hope this helps
User avatar
admin
Site Admin
Posts: 3382
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
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Re: Masking Q?

Post by admin »

Mitch44 wrote:Why is it that when im done with Mask, the button keep flashing green , and ClEaR, Cancel, Keep, does not not shut it off. its like its telling me something is not finished..;;;any ideas.
Hi Mitch,

Clear, Invert, Keep will reset the mask to 'all pixels on'.

If a mask other than 'all pixels on' is active (e.g. not all pixels are treated equal), then the Mask button will be highlighted to remind you of this fact. In addition the current active mask will flash 3 times, to let quickly show you wich pixels will be affected and which won't.
Ivo Jager
StarTools creator and astronomy enthusiast
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