Jester TLXtra and 16 bit dimmer channels

[invisible]

Hello,

I'm trying to set up some Cameo Root Par 6 in 11ch mode on my Jester TLXtra. In this mode they support a 16 bit dimmer on channel 1 (MSB) and 2 (LSB); I created the fixture with the Fixture Type Editor, selected 16bit for the dimmer, and assigned the two channels accordingly.

When I load this fixture into the console it seems to only use 8 bit though (very noticeable on LED spots, as there is a significant jump in brightness between 0 and 1%, which is exactly why there is a 16 bit dimmer in the first place).

According to the manual: "16-bit parameters are displayed on the desk as two sets of values (eg 127-255) to indicate the level of both channels", but my desk only displays 1 value (0-100%) on the dimmer wheel. In fact it almost feels as if the dimmer doesn't even use the full 8-bit resolution but actually "%".

What am I missing?

regards,
  Stephan

[kgallen]

Hi @invisible

It sounds like you’ve defined the fixture correctly.

Are you testing this by pushing a fader? You will probably find that the fader has 8 bit resolution. However if you programme a cue with a fade you should find that the console fades with 16 bit resolution. 

That is what happens on my FLX - 8 bit on the fader, 16 bit from a memory.  

Here’s a thread where we were talking about this (FLX-S in this case):

 

[invisible]

Yes, I've tested it by programming a cue list too, the brightness has a noticeable "jump" when the spot fades in/out from/to black, which is consistent with only the "coarse" dimmer channel being used.

For testing I also created the fixture with MSB/LSB reversed, there I would expect massive flickering while the fade is running (as then the "coarse" dimmer channel would cycle through all possible values) — this does not happen.
I also noticed that the Fixture Type Editor prints a warning about channels being of WORD type (i.e. 16bit) when I save the file.

When I have more time I will also cross-check what happens if I configure channels 1+2 as something else that has support for 16bit values, e.g. pan/tilt, and then "move" the fixture...

The FLX is a much more recent console (about 10 years younger than the Jester series), and the software is completely different; so I don't think it makes sense to compare the behavior between them.


I wish manufacturers would release the firmware source code of discontinued products, so that the community could more easily check & fix such issues...

[kgallen]

Hi

Do you know the fixture will actually dim to/from zero smoothly? I have lots of different LED fixtures and only the most expensive (some Philips/Selecon fixtures) even remotely dim ‘smoothly’ to/from zero, and even then not as good as tungsten. 

Try patching the two intensity channels onto two faders patched as dimmers and see if the LSB fader gives you a smooth fade to/from zero.

Commercial manufacturers are never going to release the source code of their products. It’s their IP and they wouldn’t want the bad press or support burden of scores of amateur hacked branches of code being out in the wild.

The Fixture Software giving a warning about intensity being a WORD is normal and is a useful confirmation.