# Starless Processing

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Yay!!!   It worked.  Now, to perfect it.  There are several Pixel Math formulae I have found that replace the removed stars.  I happen to like this one

~(~starless*~starsonly)

Does anybody have a better one?  I also tried

(A^N + B^N) ^ (1/N); and

iif((a<=0.01),a,001);~(~b*~a)

Here is my NGC 6888 image with no stars--this is the very first image that I used the starless processing technique on.   I decided to make a new thread as this one is dedicated to the Pixel Math formula and the other thread got so long it became cumbersome.   Anyway--Thanks again to the folks that lead the horse to water....thankfully I had the courage to drink.

and here is the image with the stars replaced using the above first formula

Edited by Rodd
used capital S in formula in error
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8 hours ago, Rodd said:

~(~Starless*~starsonly)

This works rather well - just tried it on one of my images - thanks for the heads-up Rodd.

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This works rather well - just tried it on one of my images - thanks for the heads-up Rodd.

Thanks Adrian. I am glad you find it useful.  I really enjoy the starless workflow.  I am so glad I had the courage to try!

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Interesting. Ill have to give this a try.

Not sure what the variables are, but all that I have done before is separate the stars from starless, work on each, combine starless and stars in PM, then apply EZ star reduction using the Adam Block method.

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25 minutes ago, juno16 said:

Interesting. Ill have to give this a try.

Not sure what the variables are, but all that I have done before is separate the stars from starless, work on each, combine starless and stars in PM, then apply EZ star reduction using the Adam Block method.

They are pixel math equations. What formula do you use?

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Hi Rodd,

I am way on the basic scale!

combine starless and stars (images) in PM, then apply EZ star reduction using the Adam Block method”.

This is where I am and so far, it works for me. Very basic.

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1 hour ago, juno16 said:

Hi Rodd,

I am way on the basic scale!

combine starless and stars (images) in PM, then apply EZ star reduction using the Adam Block method”.

This is where I am and so far, it works for me. Very basic.

I assume PM means pixel math. You have to use some formula with Pm.

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I simply meant in PM starless (image name)+stars (image name) = create new image.

So, with the combined star and starless image, I then use the EZstar reduction and Adam’s method to reduce the stars.

Simple and works for me.

Jim

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1 minute ago, juno16 said:

I simply meant in PM starless (image name)+stars (image name) = create new image.

So, with the combined star and starless image, I then use the EZstar reduction and Adam’s method to reduce the stars.

Simple and works for me.

Jim

Simple sure, but combining with a basic addition can often lead to clipped stars. The first formula, posted by Rodd above, avoids that (I think it was a recombination method posited by @steppenwolf, or at least, he's the first person I saw publish it).

As a side note @Rodd, have you tried the GHS script in PI? Takes a bit of learning, but on the couple of images I've used it on, it's basically negated the need for seperate nebula and star image processing as it helps control stars very well during stretching.

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3 minutes ago, The Lazy Astronomer said:

Simple sure, but combining with a basic addition can often lead to clipped stars. The first formula, posted by Rodd above, avoids that (I think it was a recombination method posited by @steppenwolf, or at least, he's the first person I saw publish it).

As a side note @Rodd, have you tried the GHS script in PI? Takes a bit of learning, but on the couple of images I've used it on, it's basically negated the need for seperate nebula and star image processing as it helps control stars very well during stretching.

No, I have not had a ch  as nice to try it. I will have to give it a shot

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Thanks guys. I should have stayed in my lane.

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9 minutes ago, juno16 said:

Thanks guys. I should have stayed in my lane.

Nonsense. What fun would that be

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I need to try that. The way I have been doing it is to just do starless+stars.  Or sometimes I do starless+(0.6*stars)

I did think that for a sophisticated piece of software my formula was a bit basic

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1 hour ago, Chefgage said:

I need to try that. The way I have been doing it is to just do starless+stars.  Or sometimes I do starless+(0.6*stars)

I did think that for a sophisticated piece of software my formula was a bit basic

I don't know--I just realized that Starnet (as apposed to starnet2 or starxterminator) does not include all stars it removed on the starsonly image.  Tiny ones are missing (or are very dim).  So what it turns out to be is a form of star control.  When you add back the stars using the formula I provided and compare it to the original image--the stars will be fewer, fainter, and smaller, which can be good things, no doubt.  But sometimes its too much star control, and some stars that one would like to be present are not.  At least your formula prevents this--you get a 1:1 exchange.    Maybe combining the formula in a way that allows one to weight one side or the other depending on the image.  But that is beyond me...

"Damn it Jim, I'm a doctor, not an engineer!"  Star Trek OS

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On 07/06/2022 at 15:11, Rodd said:

I don't know--I just realized that Starnet (as apposed to starnet2 or starxterminator) does not include all stars it removed on the starsonly image.  Tiny ones are missing (or are very dim).  So what it turns out to be is a form of star control.  When you add back the stars using the formula I provided and compare it to the original image--the stars will be fewer, fainter, and smaller, which can be good things, no doubt.  But sometimes its too much star control, and some stars that one would like to be present are not.  At least your formula prevents this--you get a 1:1 exchange.    Maybe combining the formula in a way that allows one to weight one side or the other depending on the image.  But that is beyond me...

"Damn it Jim, I'm a doctor, not an engineer!"  Star Trek OS

On my next image processing I am going to try your formula definitely.  I am keen to see the difference.

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