Hello! I just downloaded Krita and I've been trying to find a solution to this problem, but I don't understand if it's a common problem or not. I'm using a Lenovo Thinkpad 2-in-1 convertible laptop with the Thinkpad stylus and Windows 10. When I use some brushes (airbrush for example), the lines become dotted unless I go really, really slow. This doesn't happen with the basic pen. I tried smoothing (in the Tool Options bar), and the only thing that works is using the stabilizer with distance at the lowest and delay turned off. This makes the line a lot smoother, but not entirely smooth, and it creates a pretty obvious lag. Here's a picture for reference:

Also, I use Krita in Swedish so I hope all the terms are correctly translated.

What can I do to solve the problem? I'm not using OpenGL (it wasn't even default for me), and I've tried both WinTab and Windows Ink for Tablet Settings, but it doesn't help.

Does it look like that if you use the Basic-2 Opacity brush? Does it look like that if you use a mouse or the trackpad?
Have you tried disabling Windows Ink at the Windows OS level when using Win Tab? (Remember to restart krita when you make any changes in this area.)

If you do Settings -> Configure Krita -> Tablet settings icon then click the big Open Tablet Tester bar, you'll get a small tablet tester window. Reposition it and drag it out by the corner handle so it fills the screen. Then draw quickly on the grid area at maximum pressure drawing circles. In the section at the right, you'll see your stylus output. Is is consistently P=100% (pressure value)? You can Clear the listing and do it again as often as you like and can scroll up and down through the log of the stylus record.
If you draw at a constant medium pressure, is any pressure variation small and smooth?

That's all I can think of at the moment so please try all that and let us know what happens.

It was the WinTab/Windows Ink thing that was the problem! I really did think I had restarted Krita in between, but apparently not. I double-checked this time around now, and when I changed it back to WinTab it was all dotty again. So changing it to Windows Ink was the solution.

Thank you for your answer, even though it apparently wasn't really a problem as much as it was just a mistake from my side. I guess I'll still leave this post as it is, in case it can be helpful for someone else.

How did you disable windows Ink?

I'm having the same issue on a Yoga C940 and i'm having trouble figuring out how to disable it.

The choice between krita using Wintab or Windows Ink is made in Setttings -> Configure Krita -> Tablet settings, by option tickboxes.

If you use Wintab then you may need to disable Windows Ink in your tablet setup/config utility and also at the Windows system level. That is somewhere in your Windows settings, maybe by left or right clicking the Windows Ink icon on the taskbar. (I dont usually use Windows and I can't remember the details.)