Pixel mapping using RGB colour..

Thu Jan 24, 2019 12:47 am


Is it possible to get Sky Panels in 'calibrated colour' (that use Kodak Pro Photo Color Gamut / ESTA standard E1.54.) to match the colour displayed on my computer monitor?

I'm using Mbox media server software that runs on Mac OS X to generate RGBw values for an array of Sky Panels pixel mapped on my screen. I run a video clip and the software samples the screen pixel the lamp is on... If i play a solid white clip and read the DMX values I can see R=255, G=255, B=255 & W=255. If I use more subtle shades the match is not so accurate. If I try just RGB (no White) the results are worse.

If I use OS X colour meter app to read a screen pixels RGB values and observe the same RGB DMX values [0>255] going to the lights, I'm finding the lights will be quite different to whats on the screen.

I believe Mbox uses sRGB natively, as this is what the macOS uses. Everything gets passed through the software as sRGB, and I believe the output gets converted to match the colorspace of the monitor. I'm asking if I could get hold of this 'Kodak Pro Gamut...' and choose it as a display profile in system settings, could I get a closer match?

Hope this makes sense - thanks for any suggestions. D
Posts: 4
Joined: Thu Jul 26, 2018 4:37 pm

Re: Pixel mapping using RGB colour..

Thu Jan 24, 2019 2:40 pm

Hi Bockswhite,

Thanks for your post.

The RGBW Calibrated Color Mode is using the Kodak ProPhoto color space and follows ESTA E1.54. That being said, of course the SkyPanels gamut does not cover the entire ProPhoto color space but does cover a majority of it.

With the latest firmware for SkyPanel (FW 4.1) you are able to set the white point for the color space by changing the CCT and G/M point. This will allow you to precisely match your reference white when RGB values are at 255, 255, 255.

You can change white point using the onboard controls by enabling the RGBW Calibrated Color in the menu settings (Main Menu -> Light Control -> RGBW Color Space -> Calibrated Color) and then going to the RGBW mode screen and scrolling to the right (past the RGBW parameters) until the CCT and G/M parameters appear. Or by using DMX you can use any CCT + RGBW DMX mode and then use the CCT and G/M channels to adjust the white point.

I hope this is helpful and solves you problem. Please let us know if there are further questions.

- Mike Wagner
Senior Product Manager, Lighting
Mike Wagner
Posts: 59
Joined: Mon Nov 23, 2015 8:42 pm

Re: Pixel mapping using RGB colour..

Fri Jan 25, 2019 1:27 pm


Thanks for the reply. I was under the impression when you cross-faded from CCT to 100% RGB the CCT value had no effect. You are saying in v4.1 this moves the white point? Cool! I'll have a look as it should help.

Posts: 4
Joined: Thu Jul 26, 2018 4:37 pm

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