When I use some colors, and set the brightness to the lowest possible with the slider in WLED, instead of getting a dim version of a color, some colors of the LED just turn off, and it becomes a different color altogether.
For example: if I use the ffa000 HEX color (preset yellow/orange), with the slider all the way to the lowest, I get a low brightness red, instead of a low brightness version of that color.
I tried how other preset colors react, it seems to be only red staying on out of the colors used to mix, though, I don’t know how relevant, 00aba2 on the lowest brightness yields a completely turned off LED strip.
I’m using a WS2812B strip, I’ve tried another WS2812B strip (I have two of the same strips), and that got me the same results.
My guess was to try and find a minimum brightness level setting, since it’s only pretty much on the lowest brightness that this happens, but I could not find one.
Each LED only has 256 different output levels so once you go “low enough” that LED’s effective output becomes 0.
Gamma will make look colors more realistic but reduces dynamic range at low values.
The issue still happens during animations, even if I turn off gamma correction. Is there any way to make WLED set anything below a certain output level just simply 0?
Let me ask you a question: How does a single WS2812 pixel display Orange color at full brightness?
It does so by letting Red LED emit at full power (255) and Green LED emit at half power (127).
When you reduce brightness in half the Red LED will only emit at half power (255/2 = 127) but Green will do so at one quarter (127/2 = 63). If you reduce brightness still further down, let’s say to 1%, then you get Red (255/100 = 2) and Green (127/100 = 1). If you go below that Green will no longer light up.
The statements above are valid for linear brightness but human eye has a non-linear response and WLED tries to compensate for that. In this case Green will become 0 earlier in the process, and Gamma will modify that in its own way.
So Orange will display as Red at very low brightness due to physics of LEDs.
Yes, I understand that, but in some effects, it’s very noticeable, that a red dot just appears out of nothing (it’s not exclusive to orange), and I was wondering if there was any way to avoid this, or is this how it’s just supposed to be?
Not how it is supposed to be, that’s how it is. The only way that that would change is if the lights themselves supported more than 8-bits 256 levels per channel. And I don’t see that happening.
Instead, I would suggest looking at ways to physically darken your lights. Try a black or semi opaque diffuser.
Sadly, my issue isn’t about brightness, but having red appear in some effects where it shouldn’t. Warm whites end up just turning red as the effect fades into dark for example.
Well Blaz gave you a very detailed explanation of why that is. And you just want to argue that we don’t understand. I think ultimately the core problem is about brightness, just not in the way you are thinking.
Yeah you might be right, maybe I just don’t want to accept that, since it’s a big eyesore to me in the middle of effects, thank you for the replies!!