One jerky fixture, not the others

Ask a generic question about the usage of QLC+, not related to a particular operating system
Post Reply
ScanxTaz
Posts: 8
Joined: Fri Jun 25, 2021 8:57 am
Real Name: Thierry Parmentier

'Morning all !

Hey, small question, I've a set of fixtures, and, into them, 2 scanners and 2 lyres.

When I'm using an EFX to manage position of the moving heads, the thing is going very smooth with my lyres, while with my scanners, it's very jerky and "1-FPS'ed", which gives a very bad feeling :(
Of course, I'm defining the EFS the same way, even if I use one efx for the two set (Lyres + Scans) the lyres are smooth and the scan "jerky"....


My setup :

OS : Windows 10
QLC 4.12.4
CPU : Pentium Dual Core (not charged at all)
Lyres : Miniled spot led (cheap but working well)
Scanners : JB-System DualScan (2 heads by fixture)

Thanks for your ideas.
User avatar
GGGss
Posts: 3052
Joined: Mon Sep 12, 2016 7:15 pm
Location: Belgium
Real Name: Fredje Gallon

Do you also see this 'jerkyness' in the DMX monitor?
It could be a problem with pan / tilt of your scanners being 8 bit resolution?
All electric machines work on smoke... when the smoke escapes... they don't work anymore
ScanxTaz
Posts: 8
Joined: Fri Jun 25, 2021 8:57 am
Real Name: Thierry Parmentier

I've the feeling that the scanners are "too quick" in going at the right position, leading to a "jerky move"...
:( and no control on speed movment
User avatar
GGGss
Posts: 3052
Joined: Mon Sep 12, 2016 7:15 pm
Location: Belgium
Real Name: Fredje Gallon

Then you have to use fade-in timing added to your positions.
But in combination with the EFX engine, this will be difficult.
All electric machines work on smoke... when the smoke escapes... they don't work anymore
User avatar
sandinak
Posts: 191
Joined: Mon Apr 03, 2017 5:40 pm
Location: Yorktown, VA
Real Name: Branson Matheson
Contact:

So a few things here:
  • Using the same EFX on different types of heads can give different results .. that's the nature of the beast, unfortunately. Heads all handle the same config a little differently:
    • Some heads vertically depress to 110 degrees .. some go 360
    • Some heads can rotate 540 degrees .. some more or less
    • Most heads move at different speeds
    • Some heads can have a configured speed ... some can't
    • Some heads will compensate when moving fast to hit the end-setting by slowing down minutely .. some won't.
  • It's a shame you can't set the 'speed' on the scanners.. on many heads there's a speed setting for movement, and so if they're moving quickly you can slow em down a bit with a separate scene that just sets that .. and then combine the EFX and that Scene in a Collection
  • Sometimes DMX/Termination can cause jerkyness. Try moving the scanners to different positions in the chain; if you get different behavior .. start checking cables. You should also have a terminator on the end of the chain ( tho that won't help bad cables ;)
  • If you're not using true DMX cables ( 110 Ohms ) .. but (also) using XLR audio cables .. ESPECIALLY with long-length cables .. you'll get intermittent signal issues on some equipment.
  • Eliminate any empty cable on the end of the run if you can.
ScanxTaz
Posts: 8
Joined: Fri Jun 25, 2021 8:57 am
Real Name: Thierry Parmentier

thanks for the advices guys :) Have a nice stage ! Euhh.. A nice day :)
ScanxTaz
Posts: 8
Joined: Fri Jun 25, 2021 8:57 am
Real Name: Thierry Parmentier

btw, I'm using wireless emitter to avoid long cable and disturbance, works like a charm :)
User avatar
GGGss
Posts: 3052
Joined: Mon Sep 12, 2016 7:15 pm
Location: Belgium
Real Name: Fredje Gallon

ScanxTaz wrote: Wed Jul 14, 2021 7:45 pm btw, I'm using wireless emitter to avoid long cable and disturbance, works like a charm :)
Ow boy ... adds a new factor to the equation. You will soon know that in a controlled environment, things work perfectly. Once you get into the real world, wifi is taking all the available channels and bye-bye wireless. Jerky you said? ;)
All electric machines work on smoke... when the smoke escapes... they don't work anymore
User avatar
sandinak
Posts: 191
Joined: Mon Apr 03, 2017 5:40 pm
Location: Yorktown, VA
Real Name: Branson Matheson
Contact:

What @GGGs said ;) .. you might seriously grab a ladder and test with a cable ... I do quite a bit with wireless.. both the cheapy DMX dongle type and 802.11 .. learned my lessons .. and only use ArtNET+802.11 in short distances and very tightly configured. Really great write up on the dongles here. Strongly suggest reading for those considering the dongles.
Post Reply