SUMMARY
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When drawing without Krita's brush stabilizer feature, I'm getting line jitter on my Tab S8 Ultra. My issue mirrors the problem I've seen others report when working on other tablets. Example: https://forum.kde.org/viewtopic.php?f=139&t=161465

Drawing with the canvas zoomed far out results in jittery lines. Drawing with the canvas zoomed very close gives smooth lines. I've tested strokes in other tablet apps (Infinite Painter, Clip Studio) to make sure it's not my hand shaking and it's not. Even when I connect my Tab S8 to my PC as a pen display and use Krita on my Windows 10 desktop, the problem happens on the desktop version too.

And I know it's not just my unit, because I had the same exact problem on my previous Samsung Tablet (the Tab S7 Plus).

Anti-alias for the brush is set to 'on.' I've followed tutorials aimed at ensuring smooth lines. None of these things have worked so far. The line-stabilizer feature that's inbuilt can help, but I should not have to rely on such a feature, since the Tab S8 Ultra is capable of smooth strokes unassisted.
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STEPS TO REPRODUCE
1. Using a Tab S7 Plus or a Tab S8 Ultra, open the Krita app and create a new canvas. (Make sure brush smoothing is set to none.)
2. Zoom far out from the canvas and with a basic brush tool selected, draw a series of diagonal lines with your S Pen at medium speed.
3. Zoom in very close to the canvas and repeat the process of drawing diagonal lines with your S Pen at medium speed.

OBSERVED RESULT
The lines drawn while zoomed far away from the canvas are jittery. The lines drawn at close zoom are smoother. The smoothness of the line (or lack thereof) is proportional to the level of zoom.


EXPECTED RESULT
The drawn lines should be smooth, whether zoomed in close or zoomed out far from the canvas.

SOFTWARE/OS VERSIONS
Windows: 10
Android: (Latest version as of 10/10/2022)
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

ADDITIONAL INFORMATION
I have observed the stated problem on Krita 5.1.1 and the previous Krita version as well.