Author Topic: Blip removal ina greyscale image  (Read 7376 times)

Offline tdgm

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Blip removal ina greyscale image
« on: 2020 February 27 18:23:19 »
Hello

I ma having trouble removing blips from my greyscale images (Luminance and Ha). Is there a way to use the single hue blip removal technique using Pixel math described by Adam Block to remove the blips in Greyscale images?

Steve Herrman

Offline oldwexi

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Re: Blip removal ina greyscale image
« Reply #1 on: 2020 February 28 09:44:28 »
Hi Steve!
one idea could be to create the blip mask in the following steps.

First, use the process "Starnet" to remove all bright
small objects including the blips.
Starnet is not able to remove stars it removes
bright pixels groups only!!!!  Means it removes stars, asteroids, starlike objekts like
blips. Call it "removed bright pixels".

Second subtract from the original image the image "removed bright pixels",
this should result in an image having only "blips and stars" left,

Now you use the "real and only one" starmask generator, its
the script "MaskGen".
This creates a mask with really only stars by using the Gaia star database!!!
(Starnet and PI StarMask do not access real star databases)

So now subtract from "blips and stars" the result of MaskGen,
means, the real stars are subtracted from the "blips and stars"
and the blips only should be left.

Finally. this "blips only" mask you use for removal of the blips
with MMT as Adam did in his video.

This is one quick idea, for sure there are other ways.
The basic idea is, as we dont have another color channel for
calculating the mask, we use the real starmask from MaskGen to calculate the mask.

hope this helps.

Gerald

Offline tdgm

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Re: Blip removal ina greyscale image
« Reply #2 on: 2020 February 28 17:52:01 »
Hi Gerald

Thanks for the reply and would love to do it but update to 1.8.8.5 and now can't install the Starnet module. Follow instrutions to the letter and when I do a recursive search nothing is found. Tried on 2 differnt computers iMac and a Mac Book Pro


If any ideas they are welcomed


Steve