Author Topic: Pixelmath-change value of pixels  (Read 395 times)

Offline CharlesW

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Pixelmath-change value of pixels
« on: 2018 October 14 08:22:11 »
I have a large sensor camera with a bit of a banding problem. I’ve looked at the value of the pixels in the bands, they seem to have a k value that is generally one count less than the background. I’d like to use Pixelmath to bump those pixels up to a value that matches the overall background. Maybe even slightly randomize the spread. Would someone mind taking a stab at an expression that will cover all or part of this? Thanks.

Link to an Ha image- https://www.amazon.com/clouddrive/share/ZeEp16EC6bBEFGSYpyVgiLPiBo1Hg16WPDegknWjueY

Offline chris.bailey

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Re: Pixelmath-change value of pixels
« Reply #1 on: 2018 October 15 00:40:42 »
Charles

Are the bands in the same place on all the images? Do the bands show in a dark or flat field frame?

If they are constant something like iif(y() > 4090 && y() < 4115,$T+0.000015,$T) lessens the effect on the worst of the bands though I'm sure someone will be able to come up with something much cleverer.


Chris
« Last Edit: 2018 October 15 01:04:05 by chris.bailey »

Offline avastro

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Re: Pixelmath-change value of pixels
« Reply #2 on: 2018 October 15 01:42:21 »
Here is my try Charles, The bands are just noticeable, difficult to see at 1X1 image, I used a Oldwexi, Gerald formula to do the job, I recommend you to look at Gerald vidéo, it is a PM guru !
http://www.werbeagentur.org/oldwexi/PixInsight/PixInsight.html
Antoine
Antoine
Lentin Observatory
http://www.astrosurf.com/avastro/