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Quasar Science - Help Center

12bit vs 16bit Dimming

The new default dimming engine in Firmware 0.9 is 16-bit
Bit Depth

Bit depth is a measure that describes how smooth the transition is between the darkest and brightest tone of a color.  Generally speaking, the trade off with Pulse Width Modulation (PWM) LED arrays is smoothness of fades versus the highest frame rate a fixture's light output will support.

Not to be confused with 8bit vs 16bit DMX profiles: With all RR-R2 firmware before 0.9a the internal LED dimming engine's light output was dithered to 12-bit in order to maintain fast performance.

With the release of firmware 0.9a we have optimized performance to allow the dimming engine to take advantage of the 16-bits of resolution supported by the hardware while maintaining fast response times.

The biggest benefit will be seen at low intensities, especially slow fades at low intensities. They will look different between 0.7/0.8 and 0.9 firmware. (As-in look a lot better)

When combined with a 16-bit DMX Profile from your control source (i.e. Lighting Console) the fixture greatly benefits when fading off-white Hues at low intensities because of the 65536 steps of resolution versus the 256 steps with 8-bit DMX profiles.

Figure 1. DMX Profile resolution difference
DMX Profile resolution difference

Choosing a 16-bit DMX profile will give much smoother transitions across the color spectrum as well as fading from low to bright intensities.

If you need to match older firmware for some odd reason, you may change the RR-R2 to the 12bit engine by navigating to [Config Menu] → [Output Bits] to set the Bit mode to "12 bit" and the fixture's dimming will behave as it did with prior firmware.

That said we strongly recommend upgrading your fixtures to FW 0.9 to take advantage of the better 16-bit dimming engine.

Frame Rate

The other reason to change the Bit Depth is to accommodate the Frames Per Second your camera is recording. The default 16-bit dimming engine supports up to 500FPS or a Shutter Speed of 1/1000 second.

The 12-bit dimming engine will support up to 2000FPS or a shutter speed of 1/4000 second.

Figure 2. Bit Depth Menu
Bit Depth Menu

You can change the bit depth of the fixture by navigating to [CONFIG] ->[OUTPUT BITS] menu.