16bit DMX

[dickykitch]

Hi, are there any plans to add support for 16bit-capable DMX fixtures? As LED lamps are becoming more and more common, I'm finding many of them get very 'steppy' at the low end with 8 bit DMX, so smooth fades to off are impossible. The manufacturers solution to this seems often to be 16bit capability.

Many thanks
Richard

[dee99]

The DMX specification is for 512 channels at 8 bits each which we are unable to change, I assume you are refering to what some manufactures of lighting fixtures do and use 2 channels as a split 16bit word most commonly for pan and tilt.

To get 16 bit dimming you would need to use fixtures that support 16 bit dimming or pan and tilt. it may be possible to link 2 channels in scs as a 16 bit channel in a future release if there is demand for it. Normally the channels are called something like Pan (bits 15-8) and pan Fine bits (7-0)

We would have to designate any 2 adjacent channels as 16bit, all the fixtures I have come across have been Pan-pan fine. I have not seen any that have the fine as the first channel but the Asian creators of such fixtures contantly suprise me so we might need to accomadate that as well.

SCS would need to know which channels were linked and treat them as one for Fade and chase purposes, I think SCS would need 2 fade algorithms one for 8 bit and 1 for 16 bit. This would be the least processor intensive method.

Best regards, Dee.

[dickykitch]

Thanks Dee, yes that's right I'm talking about the technique of using 2x8-bit channels to provide 16-bit control. Whilst most common on moving heads, I'm finding it appearing on the dimmer channels on other types of fixtures, as well as stand-alone drivers for LED modules etc. And as you speculate I have seen units that expect course/fine and others (though much less common) that want fine/course, so the ability to swap the channels around would probably be needed for maximum compatibility with Chinese products.

In my day job we manufacture LED products (mostly for signage applications rather than entertainment), and the next versions of our DMX controllers will support the 'pseudo' 16 bit control, so it would be very useful if SCS supported that at some point.

Thanks
Richard

[dee99]

I hesitate to ask but is there a secification for pseudo channels? If you know of any documentation can you please send us the link?

Best regards, Dee.

[dickykitch]

Not that I've come across no, I was using pseudo to indicate that there isn't actually a 16bit number being transmitted directly via DMX, but rather two 8bit numbers being interpreted by the receiving fixture as one 16bit value. Your description of the course channel being bits 15-8 and fine being 7-0 is probably a better way of putting it