When you are stretching images, how do you all ensure that stars don't get bloated? I know it's a simple question, but I guess there are lots of answers. An example of bloated stars ould be:
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What methods do people use to stop star bloat?
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Arcsin stretch or after stretch reduce star bloating in PS.
I reduced my gain to 0 from 100 with my ZWO ASI 2600MC camera on Orion and star bloat disappeared due to the increased full well.
I always was under the assumption the best way to reduce star bloat is to just process the stars on a separate layer after creating a starless version of the image after stretching. However, I have noticed that sometimes using star removal tools seems to affect the detail available in your actual deep-sky target as well, creating a not so flawless process. It may be better to use a star reduction method highlighted here: http://darkhorizons.emissionline.com/PSStarBloat.htm
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It is a bit of a cheat possibly, but for RGB images of HII regions where the nebula shape/detail is really the point of most interest then I tend to use narrowband Ha (or max(Ha,O3) ) signal as luminance, This preserves star RGB colour (not necessarily their relative intensiities) while greatly reducing their size, brightness and impact relative to the nebulosity. Obviously only appropriate for certain objects (e.g pacman and pelican nebulae) though. TimH
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First is to get good data. For me that means making sure that stars don't saturate.
If shooting an emission nebula, I use a narrowband filter to reduce the starlight relative to the nebula.
When process I do one of the following
If shooting an emission nebula, I use a narrowband filter to reduce the starlight relative to the nebula.
When process I do one of the following
- If the stars don't need too much reduction I use the star reduction tool in Astroart. Typically several iterations, but you reach a point where more iterations don't help and introduce artifacts
- If severe I use Starnet to take them all out. Then I average the starless picture with the original in Astroart. That is what I did below.
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you can avoid bloated star by using masked stretch for non linear transformation,
check my demo
https://www.youtube.com/watch?v=9Z0PbKzUfrE
check my demo
https://www.youtube.com/watch?v=9Z0PbKzUfrE