Q Light Controller+

I am attempting to foray into the mystical realm of Loopback control.
I have 3 fixtures that have varying max strobe frequencies, I figured I could create 3 faders, 1 for each light, and set the range so that the fader position will be the same strobe frequency on each light.
Put these in a frame with the enable feature and set the input to Lo1.
Have the faders listen to input Lo2, then have a "master" fader and button to control the strobe faders and the button controls the frame enable.

First thing I noticed, it looks like the Frame Enable feature only controls if the faders can change state, not the DMX output.
So if the faders are above 0, then a signal will continue to be sent to the lights.
I am looking for a way that the signal is only sent when the frame is enabled.
I would like to be able to set the strobe frequency with the master fader while the frame is disabled aka "blind mode", then when the frame is enabled the channel settings will be broadcast to the lights.

I also noticed that the "Catch up with the external controller input value" has mixed results.
For the fixtures that I am limiting the range of the DMX (0-196 vs 0-255), the fader will not move the full range, but the fixture that is 0-255 will match exactly.
That being said, the catch up only works when I move the master fader and it will not catch up to the value when the frame is re-enabled.

I am looking for assistance in getting the faders to "preset" their positions to match the percentage value of the All Strobe Master Fader, but only send the strobe signal to DMX when the Strobe Enable button is active.

I have attached a stripped down version of my workspace as it is over the 2MB limit for the forums.

There is an easier way:

Create a Fixture group for your WXFH, CBH9 and TRIO fixtures.
Create a RGB Matrix for this Fixture Group, Pattern = Strobe, Control Mode = Dimmer, Blend Mode = Standard, Frequency = 2.
Create a Speed Dial for this RGB matrix, set Fade In and Fade Out to (Not Sent) and Duration to 1. On the Input tab set your Range from 50 ms to 999 ms, box "ms precision" and attach your Loop Back Slider 2 as External Control.
On the next tab you can unbox everything, except for milliseconds (now you should understand why i did set the upper limit to 999 ms).

Set your Strobe Enable button to Start and Stop the RGB matrix (your slider is already set for Loop Back Channel 2).

You might consider to:
- reduce the size of your All Strobe slider widget so that you can put your Speed Dial above it.
- fine tune the Range to your likings (if you go above 999 ms, don't forget to also box the seconds on the third Tab).
- reverse the direction of the fader. Now the fastest value will be at the bottom, if you fade upwards you slow the fader down, might be that a reversed direction "feels more Natural" to you.

Hi Michel,

Thanks for this tip, unfortunately, it doesn't look like this will work for me.
I noticed that the strobe is a bit choppy, noticeably as I get closer to 50ms.
It also strobes at full intensity, which for my lights is blinding.
For example, with the WFXH, I will probably run them at about 25% intensity.

RGB matrixes have an internal computing timing. It could be better for fluent changes or strobes... I'd stick to a very fast chaser.
Limiting the output of a function can be quickly done using a frame, inserting the function you want and adding a slider in submaster mode. With the submaster, you control the intensity the function outputs inside this frame.

The main benefit of using a RGB Matrix is not only that all your fixtures use the same Frequency, they will also run in sync.

If the strobe is a bit choppy you could add a little bit of Fade: set Fade In and Fade Out to 1/8 or 1/16 (instead of Not Sent).
If you want the RGB matrix to use the levels that where set by the master Level Channels, you could use Blend Mode = Mask.

You could also have a look at Channel Modifiers (https://docs.qlcplus.org/v4/fixture-man ... properties).
That way you can make a "0 - 196 Channel" act like a "0 - 255 Channel"

Thanks for the input.
My understanding of DMX is that it is based on 40 frames per second.
With 50ms, this should equate to 20hz strobe, if no frames are missed.
This is the frequency I want at the high/fast end.

I also note that my adapter (Enttec Pro) is configured for 44Hz in the QLC settings.
I did try to change that to 40Hz, without any change in performance.

I am also using wireless dongles, I'm wondering if I might be dropping frames here, or if they can't handle the full 40 FPS?
I also wonder if my lights can truly handle 40 FPS as well?
So many variables that could be causing that stutter.

As cool as the sync feature of the RGB matrix would be, I think I would prefer to use the built-in strobe feature of the lights.
I think having a stutter would be more noticeable than the strobes actually being off slightly.

Worst case scenario, I only strobe with the WFXH as it is a fairly bright light and with 6 heads, will be the most noticeable for the effect..

Back to your original Question.
Overhere https://www.qlcplus.org/forum/viewtopi ... 185#p71185 you will find an example how you can use LoopBack to create Buttons that set Faders to a specific level.
Just play wtih the 0, 64, 128, 192 and 255 Buttons and notice how the Faders react on them.

In your situation you should change the "185 Sequences" to work on (not 1 but) 3 loopBack Channels (one for each Fixture Type) and (in step 2 of each Sequence) use the DMX value that matches with the frequency you want.
Accordingly you need to attach the proper LoopBack Channel as External Control to the Strobe sliders of your Fixtures.


By the way: if you get bored with "always using that Strobe", you could have a look at other RGB matrices, like Even/Odd, Fill Unfill, Random Pixel .. , Fireworks or Propellor.