Quasar Science - Help Center

New Profiles for Video/Media: VRGB and RGBVW

The new profiles introduced in Firmware 0.7b were created with LED Volume pixel mapping in mind and what is known as Image Based Lighting. When pixel mapping DMX data, the RGB values that you're sending to the lights are set in a certain Color Space, which is usually defined by how that video media was transcoded (i.e. Rec709, sRGB, Linear, etc).

With Firmware v0.7,(or later) you can now control the Color Space of the light to match the playback media with a single DMX parameter.

These new color spaces are found in DMX Profiles labeled VRGB (Video RGB) and RGBVW (RGB Variable White).

With RGBVW, it is per-pixel control over RGB, CCT and +/- Green with control of Global Parameters such as Spectrum, Color Space and Output level.

With VRGB, we move CCT and +/- Green into the Global Parameter column to minimize the dmx footprint of the profile.

Furthermore, these Color Spaces make use of two different color engines inside of our new profiles.  These color engines are called Absolute Hue and Relative Colorimetric

New Color Engines: Absolute Hue and Relative Colorimetric

Absolute Hue is our RGBX Spectral Science Color Engine that give you the maximum capabilities of the LED diode set. When this color engine is at 100% saturation the color temperature (CCT) has no bearing on the light's color output. This is how manufacturers traditionally saturate light inside their fixtures.

The Relative Colorimetric engine is x/y calibrated. So when the light is 100% saturated the color temperature (CCT) is calculated into final output. This means when you're changing the Color Space parameter (to Rec709, sRGB or Linear) you are in this new Relative Colorimetric engine where we maximize SSI (Spectral Similarity Index) within the color space you've selected. The light will only output color with the selected gamut.

Finally, we've merged all this into a new VRGB profile (Profile 62) that has just Red, Green and Blue locked to a whitepoint of D6500 in Rec709 with the Relative Colorimetric engine (X/Y under the hood) in a simple RGB profile.  So you can get all the color engine benefits and maximizes fixture count per universe of DMX at the same time.

Why is all this important?

When receiving video footage that will be output to your lights, it may not know what colorspace that footage was transcoded in.  So the user can now change the colorspace of the lights on the fly via a single DMX parameter.  This means more accurate and more precise color reproduction from your pixel-mapped media.

Fixture profiles 61- 66 have been optimized to work with video controllers in virtual or volume type environments. The color engine under the hood for these profiles is based on the Quasar Science X/Y color-science to provide accurate color rendition to camera.

In addition to the X/Y color engine under the hood, profiles 63 and 64 (as well as profiles 55 and 56) default to Linear Absolute Hue but allow for relative colormetric choice (aka color space) to be set by the user on the fly via a single DMX parameter.