How could I achieve this effect?

[EmbraceSmall]

So I'm trying to make this sort of gradient texture thing but I'm not sure how. Any help is appreciated, thank you!

[NinthDesertDude]

How to do this in either Krita or Paint.net (since you asked over there first)

At 100% hardness in paint.net (or using a hard brush in krita), make a circle
At 0% hardness in paint.net (or using airbrush brush in krita), at the center of the circle, click a few times to make it more transparent. Just change the radius a bit to give the outside a thicker opaque ring like you have here

In paint.net, you can alternatively fill a circle with a solid color, then use the gradient tool in transparent mode with the radial pattern. It's basically the same thing, but slightly more complicated way of doing it.

But on Krita you were asking about replicating this pattern, basically

That's a more interesting question in paint.net. Here's how I would go about it:
 - use the ellipse tool (press O, O and then make sure ellipse is selected) with shift held down to make a perfect circle. At whatever width you want that to be. Make sure it's in outline mode
 - use ellipse selection (press S, S, S) to select the inner circle (just make sure the ellipse includes the whole part inside the circle. You can have the edges fall anywhere inside the thick outline you drew earlier with the ellipse tool)

Ok, so you should have a thick outline and selection constrained to just the inside of the circle + part of the outline. Now just take the usual brush you use at 0% hardness and try to click it evenly around the circle so it creates this pattern. The circles should be large enough to reach from the outline to the far edge seen in the screenshot here. You'll get more of those little shapes that look like triangles based on how close the circles are. The closer, the more of those little triangles you end up with. It also affects how opaque it is, so make sure to try a few different opacities until you get one that's close to what you want here.

Alllll that said, we definitely need to know if it has to be at even intervals (mathematically), because that's something only a plugin is probably going to do well. Or maybe clever use of the Fragments effect... @EmbraceSmallcan you answer that?

[CircleBox]

3 hours ago, EmbraceSmall said:

So I'm trying to make this sort of gradient texture thing but I'm not sure how. Any help is appreciated, thank you!

 

Something like this? I inverted the colors because white on white was hard to see. I just had the big black circle on a lower layer, made a new circle on top, and added guassian blur. You can adjust it a bit to help make the effect. 

 

You can also try the gradient tool and use the circle, just make the secondary color have some alpha via the 'More' button on the color tab. 

[EmbraceSmall]

@NinthDesertDudeI did your paint.net solution, but I came across a problem. The gradient when starting in the center goes high to low, is there any way to sorta reverse that and go from low to high?

[NinthDesertDude]

Maybe there's a miscommunication. What I'm saying should be all you need to get it to work: