Showtec 136 Dimming

[billy bobinski]

Hi There All,

 

I have recently bought a Showtec 136 for small shows and am having trouble with the master dimmer. The manual says that this gives you overall control of dimming on both the parcan side and the moving head side, but for the life of me I can't get it to dim the movers, although at the moment, I've only got it rigged up to a couple of icolour changers and parcans. Everthing else on the desk is dead straight forward.

 

Does anyone know whether there is a hard patched channel reserved for the dimming on the movers routed to the master dimmer, and if so, can it be changed, 'cause it doesn't mention a thing in the destructions.

 

Any help or ideas on this would be greatly appreciated.

[adam2]

In general moving lights cant be dimmed, they almost allways use a discharge lamp.

Allmost all discharge lamps are non-dimmable, and the handful that can be dimmed require specialist equipment, not a standard theatre dimmer.

 

Most, probably all, moving lights have a feature wherby the light can be dimmed mechanicly, or totally obscured. This is done by partialy or completly blocking the light path with a shutter or filter etc., not by electricaly dimming the lamp.

This would be controlled by DMX or similar means, the lantern should be supplied with "hard" that is non dimmed power.

Connecting a mover to a dimmer is liable to break the light or the dimmer or both.

 

Some venues use differing connector for dimmed and non dimmed power, to reduce the risk of mistakes.

[dirkenstein]

Hmmmm...^TM Ynot.

 

A Showtec Light Desk Pro 136 seems to be a small lighting controller with a desk-like layout, for 8 'pars' (e.g. 8 dimmer channels) and 8 'scanners' (e.g. moving lights with up to 16 channels each), which outputs MIDI and DMX.

 

It requires separate physical dimmers to control any standard stage lights or parcans without built-in DMX control, so you'd hardly describe it as a 'dimmer'. I assume your PARs either have built-in dimming or you have a separate dimmer pack controlling these connected via DMX. Are you using normal or LED PARs here?

 

It does however support some form of master intensity control for both PARs and 'scanners', so it can obviously adjust an 'intensity' channel for the scanners/movers. Unless it's cleverer than it looks, I doubt it can generate 'virtual' dimmer channels for fixtures that only support RGB without a master dimmer channel. I'm also not sure that the master intensity control is anything more than a 'blackout' button.

 

The questions I can't answer without the relevant manuals (and those aren't available online) are:

 

a) If by icolor you mean the iSolution iColor 3 or iColor 4 colour wash fixtures? They should have a master dimmer channel in DMX mode. I however, have no idea where it is (as in which offset it has from the DMX base address of the fixture), or what mode they need to be in to use it. Can you control them at all? Is it just the intensity that doesn't work?

 

b) How do you tell the Showtec what fixture you're using on a given set of DMX channels? Does it have a library, or some sort of editor where you assign each 'scanner' a particular function per DMX channel?

 

c) If you're talking about some of the iMove el-cheapo moving head fixtures, be aware that a number of these with discharge lamps don't have any sort of dimmer function at all. Not even a non-proportional on-off douser shutter. I have free access to a couple of these, but I've never been tempted to borrow them for that reason, and because of apparently exceptionally poor position repeatability.

 

Hope that gives you a place to start looking.

[billy bobinski]

Cheers to you Both,

 

I'm sorry that I wasn't as clear as I could have been, but to be a bit more specific, here goes;

 

I am using the 8 conventional channels on 2x 4 channel DMX dimmers, and the faders on the desk are hard patched to channels 129 to 136, with all channels up to that reserved for the 8 fixtures with 16 channels each. These channels can all be assigned to the individual faders on the moving fixture side of the board.

 

The washes are icolour 4 and these are assigned channels 1 to 4, 4 being the dimmer control channel.

If I use a different fixture with (as you say Adam a shutter rather than electronic dimming), the dimming channel being ch 6, I assume I would need to assign fader 4 on the washes and fader 6 on the movers to the Master Dimmer fader somehow, obviously if I have patched those channels to those faders. (There is an overall master fader besides a standby button for the cans and a blackout for the lot).

 

It is this bit which I can't get my head around as the book gives no indication of whether this is the case or not, but it definately says that the master is what it says it is.

 

And, by the way, there is no fixture library, it is all patched manually.

 

It would be good to get this sorted, because it,s not a bad compact desk for the small stuff, but if not, I,ll live with it.

 

 

Cheers!!

[Richard CSL]

I havent worked with this particular controller before , but with a similar unit, it was necessary in that unit to assign the pan and tilt channels to the two jockey wheels. After they were assigned the head could be controlled by the wheels. On reading the instructions for this unit, it mentions assigning the blackout to the moving heads.

 

so after sifting through the manual it would appear the section relating to blackout assign channels is where you should be looking . from memory I think it was page 11. I assume that you assign the relevant shutter channel to the blackout and this will automatically include the master dimmer. Even though it doesnt say so in the manual.

 

good luck.

[billy bobinski]

Thanks a lot for that Richard,

 

I'll give that a go tonight and hopefully should get it sorted, because it's the desks first trip out this weekend. I knew that the function must be there somewhere and it wasn't me going mad!!

 

Thanks All. :D

[Richard CSL]

Having just looked at the instruction manual again in more depth. There is no master fade fro the moving heads only assign joy stick. so my thoughts on this now are, while playing back a chase or cue select the heads then bring down the slider associated with the shutter.

 

Another idea would be to create a scene bank with two scenes . 1 with shutters fully open and another with DMX value 1, then run this in manual mode along side the other chases add cross fade to the stored scenes and there you have a full fade in / out. you could also assign the 1 value to the dimmers so everything dimms down at the same time. this is assuming different chases can run in either manual or speed / fade mode.

 

not sure from the manual will investigate further.

[billy bobinski]

Cheers, Richard.

 

I was thinking along those lines because when setting up chases you can add a timed fade as one of the steps in the chase, so as you say, if I were to use a chase sequence as a set of scenes, with a fade in / out at the start and end, that would give me the control I need. (I think )

 

Thanks a lot anyway, it's another idea for me to play with.