If I try to use the auto shrink for stars in this RGB image, will the mask protect the background elements of the galaxy, or will the stars in M33
be shrunk as well?
Obviously I don't wish the latter, so would I need to manually pick stars to shrink to be safe? The large yellow ones are the main culprits when seen at a higher resolution and there aren't all that many of them.
Auto star shrink
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Auto star shrink
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- Capture M33.jpg (64.08 KiB) Viewed 4903 times
Re: Auto star shrink
You create the mask you want on the stars you want, you have the control
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Re: Auto star shrink
right. I don't know how to do that.
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- Posts: 33
- Joined: Mon Jul 13, 2020 6:59 pm
Re: Auto star shrink
In the example below, I just want to shrink some of the bright, bloated stars.
But when I try the auto method, the galaxies in the group are green along with the stars.
I have tried several times with a lasso mask to circle the problem stars, or to circle the galaxies. But I can't figure out
how to tell Star Tools to shrink ONLY the stars and leave out the little galaxies.
Can someone tell me simply what the steps are?
Yes, I stipulate I am dumb to not know how to do this.
But when I try the auto method, the galaxies in the group are green along with the stars.
I have tried several times with a lasso mask to circle the problem stars, or to circle the galaxies. But I can't figure out
how to tell Star Tools to shrink ONLY the stars and leave out the little galaxies.
Can someone tell me simply what the steps are?
Yes, I stipulate I am dumb to not know how to do this.
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- M77 group.jpg (55.42 KiB) Viewed 4396 times
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Re: Auto star shrink
So here, I have got masks over mostly just the stars I want to shrink with the little galaxies excluded. Looks like it would work but...
what do I do now? If I press the obvious "shrink" tab, the green masks shrink, not the stars. So this is where I am stuck. I could do this backwards, and
just mask the galaxies, perhaps that's more correct. But then, same thing, how do you execute the shrink to actually happen?
what do I do now? If I press the obvious "shrink" tab, the green masks shrink, not the stars. So this is where I am stuck. I could do this backwards, and
just mask the galaxies, perhaps that's more correct. But then, same thing, how do you execute the shrink to actually happen?
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- M77 star mask.jpg (55.22 KiB) Viewed 4389 times
Re: Auto star shrink
Don't use the 'Shrink' button within the mask module - that's for changing the size of the mask.
To change the size of the stars, having created your mask, 'Keep' it and then, when back on the main page, select the Shrink button there: Here's what I got when operating on your image above, not perfect by any means, but have a play with the iterations and other parameters in the Shrink module:
To change the size of the stars, having created your mask, 'Keep' it and then, when back on the main page, select the Shrink button there: Here's what I got when operating on your image above, not perfect by any means, but have a play with the iterations and other parameters in the Shrink module:
Skywatcher 190MN, ASI 2600 or astro modded Canon 700d, guided by OAG, ASI120, PHD2
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- Posts: 33
- Joined: Mon Jul 13, 2020 6:59 pm
Re: Auto star shrink
Thanks.
Of course I was using the "Shrink" tab. I didn't try iterations, so I will do that. What you did is an improvement. I read that SCTs and RASAs like mine are prone to bloated stars and halos.
Of course I was using the "Shrink" tab. I didn't try iterations, so I will do that. What you did is an improvement. I read that SCTs and RASAs like mine are prone to bloated stars and halos.