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What is causing this block pattern?

Started by pgseye , May 16 2025 02:30 AM

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5 replies to this topic

#1 pgseye

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Joined: 12 Mar 2025
Loc: Melbourne, Australia

Posted 16 May 2025 - 02:30 AM

HI All,

Wondering what is causing this pattern after gradient extraction, star separation and stretching. This image was taken on a Fuji mirrorless camera with a Samyang 135 mm lens.

Thanks,

Paul

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#2 maxsid

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Loc: Sunnyvale, CA

Posted 16 May 2025 - 03:45 AM

Try to extract stars after the initial stretch (not before)

Edited by maxsid, 16 May 2025 - 03:46 AM.

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#3 Lvansoo

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Joined: 25 Aug 2021

Posted 16 May 2025 - 03:47 AM

What star removal program are you using?

Both StarXTerminator and StarNet work by dividing an image into "blocks", analyzing each block separately for stars, and then blending the starless image "blocks" back together.

If you're using StarXTerminator, try checking the "large overlap" option before running StarX.

For StarNet, try running star removal after stretching the image. Sometimes that will work.

Hopefully this helps!

- Lyle

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#4 soojooko

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Posted 16 May 2025 - 06:43 AM

If you're using StarXTerminator, try checking the "large overlap" option before running StarX.

Yep. I can confirm this. I have seen the same grid pattern when using StarX on images with dense starfields. "Large Overlap" fixes it - but also adds considerable time to the process.