Rebelle badly needs some dry/scumbling brushes

Hi @LunatiqueRob,

"BTW, why is it that in Brush Creator, often there are some parameters that are grayed out and cannot be changed, such as Pressure Size/Opacity, or Canvas Paper Texture Strength? But it differs from brush to brush, as some do allow those parameters to be changed. What determines this?"
-- When a parameter in the Brush Creator panel is greyed out, most of the times it is because this parameter uses its curve settings instead of the slider settings (curve editor is the icon next to the slider):

To be able to use the slider instead, click the X button in the left bottom side of the curve editor. This will change your selected brush, so to put it back to the previous state, you'd need to reset the brush changes.

"Also, there's something else I can't figure out. There are some brushes that have shapes and grains that are not in the default library if you click on shape or grain to try to find them. Where are these actually stored? I looked in the brush categories folders and they're not in there."
-- Not all shapes and grains are available. You can create and add your own shapes and grains to the library anytime.

Hope this gives you more insight!

Thanks so much!

Hi Rob,

Would you mind sharing the dry/scumbling brushes that you have come up with so far please? 

Sure. Here they are: https://1drv.ms/u/s!AuJvJJ14eSzGhaMsBUjRf52OQB66Ug?e=wC8PRx

The forum didn't create a clickable link automatically, so here it is again. (Can't wait for us to migrate to the new forum. This one is just terrible, with very limited features.)

https://1drv.ms/u/s!AuJvJJ14eSzGhaMsBUjRf52OQB66Ug?e=wC8PRx

Great brushes, thanks a lot!

That's kind of you Rob, thanks! 

Pardon me (I realize I may be late to the party here but I wanted to try and help if possible!)
The short answer is I agree, Rebelle probably doesn't have a pack like you want by default, the long answer is you can definitely make those!

I had a very similar issue where the default Rebelle brushes (while beautiful) weren't getting the specific shapes and styles of mark making I wanted, so I spent a weekend batch-making a ton of custom brushes (mimicking what I had in Photoshop and Clip Studio Paint).
Almost every brush I made came out perfectly if not improved so here are my thoughts.

Firstly If you haven't already watched the brush creator tutorial series from the Escape Motions youtube channel it is well worth your time!
I've made brushes in several other programs but I didn't understand how to fully utilize rebelle brush creation untill I watched the tutorials.
Link here - https://www.youtube.com/watch?v=9psTrAfhJcM&list=PLUuRcU19WlxZstZs73JQXEyRZrVzZFbCK

Secondly looking at the examples you posted from Photoshop, Artstudio, Procreate, and Infinite painter, I don't see anything that doesn't look doable in Rebelle.

One of the biggest roadblocks I found to making those rough / gritty / dirty scumbling kinds of brushes was simply the tip-shape. Rebelle doesn't come with a lot of wild "scumbling" shapes so I think it would definitely be worth your time to import some of your favorites from other programs.

You can't import Photoshop brushes directly so the quickest way I found to do it was "in bulk".
Start by making a (256 x 256) pure black square canvas in Photoshop (or any desired program), and on a separate layer "stamp" the brush tip shape in pure white as close as you can get to the edges without going over the sides.
Sometimes it helps (especially with brushes with odd stamp-shapes) to have a second canvas open where you can stamp freely (without having to get it perfect in the border the first time) then re-size it to fit the black square.
It's important to "stamp" not smear the tip when you press down, some brushes are sensitive and it might take a couple of tries but you want the tip shape not the full stroke.
Once you get the stamped imprint the way you want it, save the 256 X 256 file as a PNG but don't close your canvas.
Turn off the layer with the white paint (so you have a clean black square again) and just rinse and repeat making a new clean layer for all the brushes / stamps you want from that program.

Once you have your desired brush tips you want to put them in the "shapes" folder wherever rebelle is installed for you.
Idk what system you are on, but for me (running windows 10) it's
YourUserProfile>AppData>Local>EscapeMotions>Rebelle5>Brushes>Shapes

Now all you have to do is find a setting or two or three you like for the scumbling brush, try different combinations of jitters and play around with the curve editors so you can specify exactly how and when the brush makes certain marks. (those are going to be some of your best friends for those "messy" effects and so will the "Rotations". (None, Follow trajectory, Pen Tilt, and Pen Rotation.)
"Smudge" and "smudge quick strokes" vs no smudge may also be worth looking at.
(Again if you haven't watched those tutorials they are lifesavers for figuring out exactly what you need to tweak.)

If you are able to find a couple "scumbling" settings you like, just make coppies of the brush and add the imported tips.
(Remember to save the setting as the new brush default when it's just the way you want it in case you ever have to revert it.)

And thats about it! The effects you want are possible, but It will take some time and customization. Bulk-creation makes it much faster, I Imported almost 300 but it only took a weekend of playing around and i'm extremely happy with the results, so for me that was well worth the time and effort i'm saving not having to go back and forth between programs.
IMO part of ones journey as an artist is the quest for those perfect comfortable brushes. I'm happy you seem to have found some that work well for you in other programs, and I hope you find success finding or creating some for rebelle.
And hey, if you do make some scumblers you love maybe upload them to the free assets brush library and become the scumble brush change you want to see in the world! (I would share mine but unfortunately the tips I used came from a paid PS brush pack. If I make some completely custom i'll let you know.)

Good luck and happy painting! 

"The problem with Rebelle's brush engine right now, seems to be that when decreasing the load, the paint doesn't actually dry out and create this effect--instead, it tends to just decrease the opacity of the brush"

This is incorrect, thankfully. All of the default brushes aren't good at doing this, but Rebelle brushes can actually 'dry out'.

These are 2 of my brushes in Rebelle 5:

The settings to tweak with are 'pressure', 'loading' and 'opacity curve editor'. This can even be achieved with paint and blend brushes, which gives a lovely effect. I have made many brushes like this and I assure you, the effect you're after is possible.

You'll also notice the brush on the right is one of the ones you have in photoshop - plastic wrap (I think I have the 70 px version, you seem to have the 40 px, but it's essentially the same). This is because this, and most of my brush shapes are imported from photoshop brushes, because there are PS brush packs wayyyy more suited to this than Rebelle default shapes, such as the Yizheng Ke or Wangjie Li packs.

Basically, how it works is that if set up correctly, only the most opaque parts of the brush will paint. This is the same as in photoshop, just slightly harder to set up.

I'd be happy to make a brush for you and show the process, so you can replicate it with other brushes.

Hope this helps

woops my bad, didn't realise there were 3 pages on this thread lol. anyway, I still think that the 'drying out' issue hadn't been addressed so I hope my reply can help with that.