Fixture Definition for complex pixel bar (feat. lime & uv LEDs)

[frankfunk]

Hey guys,
I'm trying to create a fixture definition for the ADJ UBL12H pixel bar. The problem I'm running into is that the bar not only uses RGB and Amber LEDs (which can be addressed by Resolume), but also Lime and UV. I don't neccessarily need to use them, but in all available DMX-modes the channel order is as follows:

Pixel 1 Red
Pixel 1 Green
Pixel 1 Blue
Pixel 1 Amber
Pixel 1 Lime
Pixel 1 UV
Pixel 2 Red
Pixel 2 Green
...

My understanding is that I can only add custom parameters before or after the pixel channels, but not inbetween. So it seems that it's not possible to create a fixture for this device, because I can't add two custom channels between each pixel. Am I right or am I missing something?

I could of course create a fixture for each individual pixel, but with 34 lights x 6 pixels each this would be a very tedious process.

[Zoltán]

Indeed, custom channels only go after or before a pixel block.

Duplicating fixtures is easy and fast, place the first one where you want to start the fixture in the input selection, then do an Alt+drag duplicate to the next pixel position, then hit Command(control on windows)+D do create the next duplicates with the same offset.
Works also on multi selection.

[frankfunk]

Returning to this year-old thread:

@Zoltán: You were right—mapping the individual pixels wasn’t as tedious as I had expected. The advanced output window is quite powerful. I used a separate "last pixel" fixture that included the additional channels.

Now, I’ve encountered a different issue that I’d like to describe here in case it helps someone else:

As mentioned earlier, the fixture requires RGBAL (+ UV) values for each pixel, and there is no DMX mode that supports RGB-only control. The problem with sending pure RGB values is that it significantly distorts color accuracy. This is particularly noticeable with pure white, which appears with a strong blue tint. The reason for this is that the fixture expects Amber and Lime to be at 100% as well when displaying white.

As a workaround, I created a shader in Wire that extrapolates Amber and Lime values from an RGB texture. Finding the right mathematical approach was challenging, but the actual implementation turned out to be fairly straightforward. I use this setup with Video Router sources. The mapping in the Advanced Output window can be a bit tedious (since you need to manually adjust the input sources for the Amber and Lime channels), but the final image quality is significantly improved.

[Zoltán]

Lime color channel on a fixture... wow.

What actual color is it though?

[frankfunk]

It's a warmer, less saturated green. In combination with Amber it's supposed to close the gap between green and red, thereby improving color rendition (as measured by CRI) and enhancing skin tones. Definitely useful in photo/video lighting, however, why anyone would implement it in a pixel bar—especially without the option to disable it—eludes me.