The Weird Saturation Thing

[mr_reidpants]

So one of the things that I've been fighting with for the entire time I've used ArtRage has been this weird chroma shift when blending that overshoots the chroma of the colours being mixed. The dark one here is an orangey brown and a slightly more yellow near-grey, and the blend is significantly more red than either colour. In the lighter pair, there's a desaturated orange and a somewhat more yellow near-white that generates a streak of near-lemon that looks green in context.



Does anyone else struggle with this? Is this a bug (like a precision issue)? Do you have tips beyond "don't mix those colours" or "manually choose your midtone?"

[DarkOwnt]

So one of the things that I've been fighting with for the entire time I've used ArtRage has been this weird chroma shift when blending that overshoots the chroma of the colours being mixed. The dark one here is an orangey brown and a slightly more yellow near-grey, and the blend is significantly more red than either colour. In the lighter pair, there's a desaturated orange and a somewhat more yellow near-white that generates a streak of near-lemon that looks green in context.



Does anyone else struggle with this? Is this a bug (like a precision issue)? Do you have tips beyond "don't mix those colours" or "manually choose your midtone?"

Hello mr_reidpants


If you do a search on my posts you will find this has been investigated, and discussed at length. It's real, and I struggle with it.


NOTE: With the advent of the custom brush in AR5, blending with paint, and with depth (AR6) has improved markedly.
My statements in this thread are outdated.

.......................


The programmers even have offered their explanations for what causes it and predictions about whether it will or will not continue to happen in ArtRage in the future.

I actually got a little spirited during one exchange and almost got banned!


I have resorted to insta-dry and a lot of thinners, essentially blending by "glazing", while taking samples (alt key) to pick desired in between colors.

Best of Luck!
DO

[Daniel Aubert]

O yeah, I also hate this...
The solution I found was to stop using the traditional tools (oil and knife). Althought I really like them, with the new custom brushes the blending works more like what we want, without this saturation shifting. Try that.
The picture below shows the settings I used to maintain a good amount of blending. The color pickup must be very low, or otherwise you are just going to be blending and adding almost no paint.
At some point I am going to share the brushes I made.

[DarkOwnt]

O yeah, I also hate this...
The solution I found was to stop using the traditional tools (oil and knife). Althought I really like them, with the new custom brushes the blending works more like what we want, without this saturation shifting. Try that.
The picture below shows the settings I used to maintain a good amount of blending. The color pickup must be very low, or otherwise you are just going to be blending and adding almost no paint.
At some point I am going to share the brushes I made.

Thanks DA!

Looking forward to your brushes!

[mr_reidpants]

The simulated impasto is a pretty big deal for me though; it's definitely ArtRage's standout feature.

[Daniel Aubert]

There is a similar problem in Krita when working with 8 bit color depth images... The blending brushes also have a weird problem with saturation. But then someone found out that if you used 16 or 32 bit color mode in Krita this problem would disappear. I don't know if this is something that the developers of artrage could take a look... just a suggestion.

Cheers.

[mr_reidpants]

Yeah, I was 99.9% sure that this was a loss-of-numerical-precision issue. If they used uint16 instead of uint8 for their colour channels this issue would effectively go away, and I'd be extremely fine with the extra memory use. Like, my 12-layer 2400x1800 painting only gets AR up to 400MB of ram, and I have 16GB in my old machine. Hell, they could use double precision floating point for RGB/height/wetness and they'd still come in under 4GB, so I wouldn't even have to moderate my chrome tab proliferation. Well, if they're naïvely implementing their undo buffers I guess double float could be bonkers.

Still: I'd gladly accept a way larger memory footprint and 4-8x cpu usage to have that oil brush work the way it should.

Also: I'm almost certainly going to try out Krita.

[DarkOwnt]

Yeah, I was 99.9% sure that this was a loss-of-numerical-precision issue. If they used uint16 instead of uint8 for their colour channels this issue would effectively go away, and I'd be extremely fine with the extra memory use. Like, my 12-layer 2400x1800 painting only gets AR up to 400MB of ram, and I have 16GB in my old machine. Hell, they could use double precision floating point for RGB/height/wetness and they'd still come in under 4GB, so I wouldn't even have to moderate my chrome tab proliferation. Well, if they're naïvely implementing their undo buffers I guess double float could be bonkers.

Still: I'd gladly accept a way larger memory footprint and 4-8x cpu usage to have that oil brush work the way it should.

Also: I'm almost certainly going to try out Krita.

Let me know what you think about Krita once you've had a chance to try it.

[HannahRage]

Like, my 12-layer 2400x1800 painting only gets AR up to 400MB of ram

I would point out that many artists like working at significantly larger sizes than that If we did nuke the performance just to refine the color blending a little further, I might have to go into hiding and stop answering support emails to avoid the raging mob.

It also requires a lot of backend work rewriting the entire colour mixing algorithm; not saying it will never happen, but it's going to depend on many other things like how bored the programmers are, and whether it actually will make a noticeable improvement. It's entirely possible to make a more accurate and realistic version of many aspects of ArtRage's Stuff... if you don't mind purchasing NASA's entire computer stock to run it and no other features coming out!

So we do pay attention to what people need, but it's often a balancing act against whether it's actually possible right now and whether it makes sense to try and do it in ArtRage at all.

[nekomata]

If they used uint16 instead of uint8 for their colour channels

if you're referring to 16 bits per channel color blending (I don't get your choice of words but whatever idc), artrage does it since 2010 (likely even earlier)
https://forums.artrage.com/showthrea...413#post274413

comparing color blending across versions (I ended up purchasing the AR5 upgrade this week after being served with a venti cup of toxic fumes with another annual c*rel p*inter release), v. 5 has been fine-tuned here and there,
dry oil brushing looks neater and cleaner than in 4.5.
this might be subjective tho.



also krita is garbage
if you're on windows, get clip studio paint and/or paint tool sai.