Brush issues with 2.10 - Printable Version

Brush issues with 2.10 - Printable Version

+- Gimp-Forum.net (https://www.gimp-forum.net)
+-- Forum: GIMP (https://www.gimp-forum.net/Forum-GIMP)
+--- Forum: Gimp 2.10 (https://www.gimp-forum.net/Forum-Gimp-2-10)
+--- Thread: Brush issues with 2.10 (/Thread-Brush-issues-with-2-10)

Brush issues with 2.10 - gimpuser23 - 10-13-2018

Hi, i was wondering what's the issue with the quality of the brushes while painting on different layers and painting with white. I'm still using Gimp 2.8, but I've also installed a portable version of 2.10, because it's easier to switch between the two in that way. I have tried out the newest original version, and the same issues occur there as well.

When you create a new transparent layer, and you paint with the Paintbrush Tool, there is a difference in painting comparing to a layer with the full (let's say white) background. Brush strokes seem to be more indexed-like, with reduced dithering on the edges. Examples bellow, one on the left is on the layer with a white fill and one on the right is on a new transparent layer:

[Image: 2ljgqrb.jpg]

Especially, when you lower the opacity and you want to build up a volume of a shade, it just looks horrific when it's indexed out.

Second problem is with using the white color. White is always indexed and non-dithered in comparison to black, no matter the situation. Also, far more stronger, especially if you are shading with lower opacity. It takes for black way too longer to build up volume, while white is strong at even 1% of opacity. Here are some examples of the white:

[Image: 24obksw.jpg]

And here it is in the interaction with the black, you can see the difference in the dither:

[Image: acs6rb.jpg]

These are all default 25 or 50 hardness brushes, all new options are left untouched. Needless to say, all of these issues are non-existent in 2.8, and I have no complaint to the quality of the brushes there. It's not just with the Paintbrush that this occurs, but also with the others including the Eraser Tool.

So is this something that happens with anyone else or is it just me? I'm using Windows 10 and all of my drivers are up to date. If this is suppose to be a normal change, then I have to say that it is a major setback comparing to the 2.8 and I can't understand why was this downgrade necessary for something that worked almost flawlessly.

I have another issue when it comes to the white color, and that is when you want to remove it in Color to Alpha option, where the removal is way too strong and out of proportion, but I've managed to 'fix' that by changing layers to Legacy. I might start a thread just for that issue in the future.

So, I don't know is it just me or does anyone else have these issues? As I've already said, these are non-existent in 2.8, and that is the reason (among some other) why I still can't completely shift to 2.10. Quality is just reduced while painting and/or shading.

Thanks.

This is how it looks like to build up volume with Paintbrush Tool while on a new transparent layer, and let's say, around 20-25% opacity. It just looks messed up, and it cannot go any darker from that although I'm using black color. It just doesn't build up in these central areas, no matter how many times you go over:

[Image: dm42mf.jpg]

There is just no way that this is supposed to be a 'normal' behavior. Or I'm missing something out of the new options.

RE: Brush issues with 2.10 - rich2005 - 10-13-2018

The eyes gave in about a quarter of the way through that, a bit like an impromptu Rorschach test.

There is a difference between Gimp 2.8 and Gimp 2.10 That is why there are legacy modes available.

This the same brush (3 clicks, same place) default mode and legacy mode.

[Image: KhDQIFU.jpg]

RE: Brush issues with 2.10 - gimpuser23 - 10-13-2018

(10-13-2018, 01:55 PM)rich2005 Wrote: The eyes gave in about a quarter of the way through that, a bit like an impromptu Rorschach test.

There is a difference between Gimp 2.8 and Gimp 2.10 That is why there are legacy modes available.

This the same brush (3 clicks, same place) default mode and legacy mode.

I've totally missed that there is legacy option for the brushes as well... but that is just so strange. I don't understand the purpose of this differentiation. I can see that Default versions have more options to them, especially when it comes to the Layer effects... could it not all be sorted together, cause it totally went over my head that you can change between Legacy and Default trying out 2.10 for the first time. Simply because the 'Default' mode in 2.8 is good for the eye and you don't have to adjust anything. Shouldn't the Legacy mode (from previous versions) be a default and you add the new ones to it, that you can switch to. If you're using Gimp for the first time and you don't know that you have to switch, you'd think Default mode is kinda ugly, so it would be a turn off...

Legacy mode is here to stay in future versions as well, right? I just can't wrap my head around this new... arrangement. Was totally unaware of it, to be honest.

RE: Brush issues with 2.10 - rich2005 - 10-13-2018

Well it is a new edition of Gimp, so some radical changes. ~~Default~~ Legacy modes are there for backward compatibility.

If you are using Gimp for art then one useful difference is the fix for RGB semi-transparency blending.

see: https://www.gimp-forum.net/Thread-Gimp-2-9-color-blending-problem

While you are still hooked on Gimp 2.8 remember that when saving in Gimp 2.10 remember to change all layers to legacy or your .xcf will not be readable in Gimp 2.8

RE: Brush issues with 2.10 - gimpuser23 - 10-13-2018

I think there are lot of digital painters that are looking into software such as Gimp and similar as alternatives to popular ones. From the post you gave me it seemed somewhat of a similar issue with someone who was interested in painting and not knowing of Default and Legacy. I don't know... I like to do a lot of black and white rendering and so far the Legacy (or 2.8) has served me quite well in that regard. You said that 'Default modes are there for backwards compatibility' and not the Legacy one, is that correct?

RE: Brush issues with 2.10 - rich2005 - 10-13-2018

My mistake, I did mean Legacy modes for backward compatibility.

RE: Brush issues with 2.10 - gimpuser23 - 10-13-2018

(10-13-2018, 04:36 PM)rich2005 Wrote: My mistake, I did mean Legacy modes for backward compatibility.

Yeah... I still don't quite understand the whole linear vs perceptual RGB thing. I should look into it more. How is this issue resolved in Photoshop, does anyone know? I don't use it, so I don't know how the brushes function there. Is it more seamless? As I've mentioned, the example with the lower opacity in the Default mode is... I'm just not satisfied with that look, even though it should be more correct, I guess.

RE: Brush issues with 2.10 - mholder - 10-15-2018

"Photoshop actually has the ability to do layer blending in linear space. To turn this “feature” on we need to hit the checkbox labeled “Blend RGB Colors Using Gamma 1.00” in the Edit->Color Settings dialog. In my version, I have to hit “More Options” to see the toggle. Why isn’t this the default setting for layer blending?"
http://www.kiransprojects.com/blog/2014/photoshop-blending-is-broken/

As best I can tell, the 2.10 default mode removes the Gamma adjustment before applying the brush strokes, and then it reapplies the gamma correction to render the brush strokes. Confusing, I think, but the math seems to work correctly. The default layer modes work well. for example the 'addition' layer mode in default adds the mathematically correct values, but the legacy 'addition' blows out the bright areas way too quickly.

http://blog.johnnovak.net/2016/09/21/what-every-coder-should-know-about-gamma/
I find the subject confusing.

https://www.youtube.com/watch?v=IFkZOtx61X4
A displaced gradient with sRBG creates a curved ramp in Blender.

https://media.fxguide.com/fxpodcast/fxg-090927-linearlight.mp3

RE: Brush issues with 2.10 - gimpuser23 - 10-15-2018

Seems like it's all work in progress... I personally don't mind both options. My thinking is that they should both remain and that the option for switching from one to another should be just more accessible if someone wants a specific result. I really don't think either should be excluded.

Thanks for the heads up on how it works in Photoshop. It's interesting that it's not a default mode there.