16-bit dimming

[Erwin Redl]

Hi there,

I'd like to start experimenting with 16-bit DMX dimming of simple RGB-LED strips for a little art project.

I usually use Nicolaudie products, e.g. ESA-PRO software with the SIUDI 7A/7B DMX interface. I found the following DMX encoder - http://www.led12345.com/16-bit-dmx-cv-decoder-for-led-dmx-controllers-p-110.html

Would that be a good hardware/software set-up? Any other recommendations?

Thanks for your help in advance!

Erwin

 

[DIYLED]

I haven't used that DMX dimmer, but it looks like an LTECH product which distributes to a lot of retailers.

One thing I have noticed is that some 16-bit dimmers have a low PWM frequency which can create aliasing effects during filming, unless you can adjust the framerate of the camera (most people's cell phones will not do this). This is due to limitations of processor clock speed. An exception may be this unit, although it doesn't explicitly state but implies that TV/film modes are 16-bit:
http://www.citytheatrical.com/products/d4-hp-dimmer

A good compromise is to use 12-bit dimmers with high refresh rates, such as these:
https://www.nledshop.com/index.php?main_page=product_info&cPath=1&products_id=1
http://www.celestialaudio.com/ca_dmx_32_V2_nfet/index.html

 

[RC4Wireless]

A good compromise is to use 12-bit dimmers with high refresh rates, such as these:
https://www.nledshop.com/index.php?main_page=product_info&cPath=1&products_id=1
http://www.celestialaudio.com/ca_dmx_32_V2_nfet/index.html

All RC4 Series 3 dimmers, which can be used both wired or wireless, provide high-resolution 16-bit dimming at 615Hz for oustandingly smooth and flicker-free LED appearance when viewed by the human eye. They are also super small, super reliable, and covered by a lifetime warranty. If you are not worried about video capture, 615Hz is perfect. Full 16-bit resolution provides 65, 536 steps on the dimming curve.

For video capture, those same dimmers deliver:
15 bit at 1230Hz (32,768 steps)
14-bit at 2.5kHz (16,384 steps)
13-bit at 5kHz (8192 steps)
12-bit at 10kHz (4096 steps -- often the sweet spot when slow-mo is required)
11-bit at 20kHz (2048 steps -- no audio interference when used near mics and pickups)
10-bit at 40kHz (1024 steps -- no audio interference, capture thousands of frames per second)

For reference, remember that a single DMX channel is 8-bit, with 256 steps. Combining two channels provides 16-bit resolution with 65,536 steps.

Current RC4Magic Series 3 firmware delivers 16-bit resolution at the dimmer output with 8-bit control at the input using RC4 Digital Persistence. You get all the smoothness without doubling the number of DMX channels you need.

RC4Magic Series 3 firmware version 4.068, which is in BETA right now, provides dual-channel 16-bit dimmer control. Any RC4 S3 user who'd like to give it a try in advance of release can contact me directly (upgrade is easy with an RC4 CodeLoader cable). Likewise for the OP, we can loan or rent you an RC4Magic S3 dimmer for evaluation.

Thanks,
Jim
RC4 Wireless