DMX/LED Pars. Does this make sense?

[grantl]

Hi,

 

This is my first post here, please be gentle. I've been looking at various websites on and off for the last couple of days to try to work out what will be the best solution for a lighting challenge I'm involved in. I'd regard myself as technical, fairly competant with audio, but not knowledgable about lighting. So I'd like to describe what I think is the best solution and then have you tell me wy I'm wrong. Thankyou.

 

What I need to achieve:

The church I attend to is organising a series of events over Lent this year, there is a need for some lighting and a small budget (600ukp) to make purchases.

 

The events are: 1. A series of readings, each one accompanied bythe illumination of a small object on a plinth. There are 14 objects spread across two buildings. 2. A chamber music concert in the round with four musicians. This will require light for each musician and some ambient lighting. 3. A small theatrical production (stage space of about 4m x 7 m) 4. An art exhibition which may require some extra illumination.

 

The considerations I need to take into account are:

I need a lot of lights for the 14 objects, so plenty of channels.

The lights need to be quiet and preferably cool.

The stuff I buy needs to be useable in the future possibly in combination with more lights.

It needs to be fairly simple so that the less technical can operate it and, maybe even set it up.

 

So I'm thinking about buying 14 LED Par56 cans from Thomann, with associated DMX/Power cables, a STAIRVILLE DMX-MASTER I controller, and some hardware to hold it all up off the ground.

I'm aware that this is not great kit but the budget constraint is a firm one.

 

So from my readings I understand that I will need 5 channels for each light and I will need to set all channels to make each light work. The stairville supports 12 fixtures with 16 channels per fixture. Each fixture uses a fixed set of 16 addresses in a contiguous block So with careful address setting on the PARs I should be able to assign two PAR cans into each of the controllers fixtures.

This will allow me to fully control a pair of cans via the faders. I think I can then save scenes with settings for all of the fixtures which can then be moved between. (As an aside it seems to me that I can get two cans to do the same thing by assigning them the same address, I appreciate that this reduces flexibility, but it makes moving the faders simpler, am I correct in the assumption?)

 

The application which I think will be most compromised/impossible with this setup is the art exhibition, I suspect that I'm unlikely to get the light colour that the artist wants from these cans. But I'm willing to sacrifice this one to provide a decent solution for the other three.

 

As a last item, I'm hoping that there will be enough budget left for a simple USB/DMX interface, this would make running the two buildings easier. But as we don't have a PC always available I don't want to use only a PC setup.

 

So, can anyone tell me where I'm going wrong, or what I have missed?

 

Many thanks,

 

Grant.

[cliveybaby]

Hello

 

Welcome

 

I would suggest enquire about the hire side of things (even then may struggle)

 

or the 2nd hand market

 

Would need a bit more info but I think you have a big ask of your £600

 

Sorry to be so negative

 

Try to focus (no pun) on the priority of each part of the shows and what is essential and not just

someone saying 'I want'

 

even though you are planning to buy a load of cheap and cheerful Pars the expense of rigging and cabling

might surprise you, and then making all of the installed kit safe and usable is something else that costs (time and money)

 

If you have specific questions I will do my best to answer

 

CB

[Sound In Gloucestershire]

can y ou get 14 led parcans and a controller for £600?

 

also not to mention all the cables, possibly stands, clamps, adaptors etc

[Davethsparky]

With regards to your patch, I'm afraid it doesn't quite work like that.

If the desk can control 12 fixtures with 16 channels per fixture that means it can control 12 differently addressed fixtures with a maximum of 16 control channels per fixture. The number of channels per fixture and the function of those channels is set by the fixture personality loaded into the desk, so if you load the personality of a fixture with 5 channels it will only output data for those five channels. You can however set as many fixtures as you like to the same address, assuming you want them all to behave exactly the same. I am assuming that the desk you have chosen behaves like the majority of desks out there.

This set up will not be as easy to use as a normal dimmers + lights set up.

 

If those pars are of the type with hundreds of 5mm leds in them, then my personal experience suggests that you will struggle to light even the smallest object effectively with one of them.

 

I would recommend that you use regular lights if you have the power available for them, fresnels are probably your best bet to light all of these situations effectively.

[smalljoshua]

With regards to your patch, I'm afraid it doesn't quite work like that.

If the desk can control 12 fixtures with 16 channels per fixture that means it can control 12 differently addressed fixtures with a maximum of 16 control channels per fixture. The number of channels per fixture and the function of those channels is set by the fixture personality loaded into the desk, so if you load the personality of a fixture with 5 channels it will only output data for those five channels. You can however set as many fixtures as you like to the same address, assuming you want them all to behave exactly the same. I am assuming that the desk you have chosen behaves like the majority of desks out there.

The desk the O/P has chosen doesn't work like that though. It doesn't have fixture personalities.

 

I like to think of each of these "Fixtures" as pages. Each page has 16 channels split between 2 sub-pages (A&B) therefore the desk could use one "Fixture" to control 16 dimmer channels or 1x 16ch Moving Head or anything in between.

 

Josh

[grantl]

Wow!

 

Thankyou for the replies, lots to think about.

 

cliveybaby: Can you suggest what I should be trying to hire as alternative? I'm tempted by the LED PARs because (a) the two rooms we are using are quite small and will have low incidental lighting and (b) once we own this we can do more the following year, maybe buy some DMX dimmers and incandescant lights to supplement what we have. If we hire then we're hiring everything forever. (I forgot to mention we have existing dullish dimmable white wash floodlights in place, sorry I should have mentioned that, but they are very forgetable things.)

 

Sound In Gloucestershire The pars are £31.75 at Thomann, (£444) the controller is about £80. So this leaves only £76 of the original budget. But I have a ton of XLR cables and power stuff from the established PA side of things. I know that mic' cable is not really suitable but for these events we will be using shoort runs (max 20metres) in an electrically benign environment, there seems to be quite a lot of anecdotal evidence that this will be OK. So with a bit of scrimping and fiddling I think the 76 pounds will just about do. I suspect there may be a budget for staging each event that I can scrape an extra few quid from.

 

Davethsparky I think the controller I'm thinking of is far too dumb for the personality stuff that you mention. You've hit upon my biggest concern though regarding brightness. Thomann do have a thirty day return policy though, so I'm going to call them for a chat about brightness and buy a couple to test with. I thgink that's reasonable if I tell them what I'm after and they say it will do the job I'll have no qualms about sending it back.

 

Thank you all for the comments.

 

Regards,

 

Grant.

[bjkered]

If those pars are of the type with hundreds of 5mm leds in them, then my personal experience suggests that you will struggle to light even the smallest object effectively with one of them.

 

I would recommend that you use regular lights if you have the power available for them, fresnels are probably your best bet to light all of these situations effectively.

 

 

Just to add my support to this I use Par 64 LEDS but find even these bright enough only as background etc on walls I do NOT use LEDs for Main Lighting

 

There have been many topics on the forum on the use of LEDS and what they give out BUt I am sorry that I would rather recomend the use of Par 56 conventional Lanterns and Lamps with dimmers.

 

Hence Look at Hire or an initial; combination of Purchase and Hire eg buy the lanterns and Lamp and Hire in the dimmers for the first event save some money and then buy the dimmers ( This is how I started )

[niclights]

You'll be ok lighting the objects with the LED pars assuming you position within a few feet or less -they're brighter than some might suggest. But as said they're not really suitable for lighting people. Partly this is because of low power over distance, but also because they are not good at 'warm' or flesh tone colours.

 

Regarding control it will almost certainly work, but not be easy. There are added complications beyond just the issue of fiddling into the the set fixture layout. It is difficult to explain but, depending on the channel definitions and how the desk works, you might not be able to fade in or out by fader (ie. it might assume there is only one 'fadeable' channel for each fixture). It is therefore possible that each scene will only be able to snap to the set values and you would also need one to turn them off.

 

Personally I would use generics throughout and forget the LED completely. You'll get much more pleasant, useful light and control will be simple. You can keep heat and power requirements low by chosing smaller fixtures/lamps (particularly for the objects) and you can reduce cost by pairing lanterns on channels, especially if they are relatively low power.

 

Ideally I'd look for a basic desk to accompany that didn't attempt to incorporate moving light functions. While you won't be able to find much in the way of programmable in budget, there are plenty of cheap simple 1-1 DMX preset consoles. If you lose the LED you probably won't need any programmable memories.

[Smiley]

(As an aside it seems to me that I can get two cans to do the same thing by assigning them the same address, I appreciate that this reduces flexibility, but it makes moving the faders simpler, am I correct in the assumption?)

 

Althougth as you mention flexibilty on independant colour change is heavily impacted by assigning any number of fixtures to the same DMX address it does reduce the number of channels required to operate. On a five channel fixture you can assign all 14 with the same address thus only using five channels. Downside is all respond identically. Groups of fixtures for selected illumination area's would probably all be assigned the same anyway. Of your total number of aquired fixtures work out the grouping first then this will dictate how many channels required. So in summary, you are correct in your assumption.

[geek3]

Wow!

 

Thankyou for the replies, lots to think about.

 

cliveybaby: Can you suggest what I should be trying to hire as alternative? I'm tempted by the LED PARs because (a) the two rooms we are using are quite small and will have low incidental lighting and (b) once we own this we can do more the following year, maybe buy some DMX dimmers and incandescant lights to supplement what we have. If we hire then we're hiring everything forever. (I forgot to mention we have existing dullish dimmable white wash floodlights in place, sorry I should have mentioned that, but they are very forgetable things.)

 

Sound In Gloucestershire The pars are £31.75 at Thomann, (£444) the controller is about £80. So this leaves only £76 of the original budget. But I have a ton of XLR cables and power stuff from the established PA side of things. I know that mic' cable is not really suitable but for these events we will be using shoort runs (max 20metres) in an electrically benign environment, there seems to be quite a lot of anecdotal evidence that this will be OK. So with a bit of scrimping and fiddling I think the 76 pounds will just about do. I suspect there may be a budget for staging each event that I can scrape an extra few quid from.

 

Davethsparky I think the controller I'm thinking of is far too dumb for the personality stuff that you mention. You've hit upon my biggest concern though regarding brightness. Thomann do have a thirty day return policy though, so I'm going to call them for a chat about brightness and buy a couple to test with. I thgink that's reasonable if I tell them what I'm after and they say it will do the job I'll have no qualms about sending it back.

 

Thank you all for the comments.

 

Regards,

 

Grant.

 

You're Really not suppose to use standard XLR cables for lighting, they don't have the right impedance for DMX standards, and can give crappy or undesirable signals. but If you can't afford to buy or rent DMX cables, then just use mic cables, they will work fine for short runs, but for long runs you may lose your signal.

[willpower]

I have used both LED and incandescent lights in a church situation. The Thommann pars will not be bright enough, especially for the chamber music concert you talk of - musicians will always want a lot of down-light so they can read the music, and very little front or side, so they can see each other and are not blinded, and it doesnt affect their reading of the music.

 

The 14 objects you talk of, how big are they? I would suggest, if they are small, using Birdies - in the service we were asked to light, the vicar wanted a spot on the alpha and omega behind the alter, and we used 2 birdies. Birdies may also be useful in the art exhibition, in that you can use 1 or 2 to boost the light on the artists work. However, they would be plain useless at both the chamber orchestra concert, and the small production, as they are so small. To this end, I would suggest, like Davethesparky, fresnels - as they give flexibility to be a spot, for the objects, yet can also flood for the concert.

 

You will find that the LED parcans are not only frustrating in their colour (as previously discussed a huge amount on this forum!), but also the spill they produce, and their lack of ability to be focused. The musicians will complain that they cannot read the music, the artists will say the artwork is not the right colour and doesn't look right, and the audience to the play will complain that the cast look ill. In the services we lit, we used the LED pars purely to light scenic features of the church, such as columns, the roof, a cross etc.

 

I think you'll find the controller you have budgeted for very annoying in a live situation. I have never used one myself, but have seen it being used - you have different banks of channels that you have to flick between, making live operation very fiddly and complicated. I would suggest seeking out a simple 24 channel DMX board where you have all your faders in front of you, and can easily move from one application to another.

 

Hope this helps!

 

Will

[Davethsparky]

once we own this we can do more the following year, maybe buy some DMX dimmers and incandescant lights to supplement what we have.

 

I would strongly suggest you go the other way around and get the conventional lights now and supplement them wit leds once the technology has improved a bit.

I have recently been impressed with the light output from some cans made with 18*3watt power led's, these may be worth getting a demo on aswell.

 

 

But I have a ton of XLR cables and power stuff from the established PA side of things. I know that mic' cable is not really suitable but for these events we will be using shoort runs (max 20metres) in an electrically benign environment, there seems to be quite a lot of anecdotal evidence that this will be OK.

 

If you have 14 fixtures with a 20 metre cable between each then thats quite a long run really, (280 metres if my maths is right)

Regardless of length you really shouldn't use non-DMX cable for DMX transmission, mic cable is designed to work up to about 20KHz wheras DMX works at 250KHz. Having said that I'm sure the majority of us have used mic cable at one time or another, and some of us have suffered for it. It is also worth noting that budget LED fixtures are developing a reputation for putting gremlins into DMX lines. I think you need to decide whether the possibilty of a few seconds of high speed rainbow fx mid concert is an acceptable risk?

Whatever cable you use don't forget to terminate the line.

 

 

I think the controller I'm thinking of is far too dumb for the personality stuff that you mention. You've hit upon my biggest concern though regarding brightness. Thomann do have a thirty day return policy though, so I'm going to call them for a chat about brightness and buy a couple to test with. I thgink that's reasonable if I tell them what I'm after and they say it will do the job I'll have no qualms about sending it back.

 

Sorry if I added confusion about the desk with my comments.

 

You could try contacting a local hire company and seeing if you can visit them for a demo of the different fixtures/lanterns.

I would tend towards 650watt fresnels as my lantern of choice for such a project with PAR56s as a cheaper alternative if necessary.

 

Which part of the country are you in? it's possible there may be someone here who could help you out.

[grantl]

All,

 

Thankyou for the replies, I really appreciate them.

 

I've decided that I'm barking up the wrong tree. With the LEDs because:

 

1. The output intensity is questionable.

2. The colours would be suitable for my band but not for art/performers.

3. The cheap desks don't provide a way of controlling the LED pars without having to page betwen faders and work in a way that has a lot of scope for operator error.

 

So I've decided to go down the route of a cheap DMX fader board, a pair of 4 channel DMX dimmers, and a pile of cheap PAR 16s. (I'll get around the lack of fader channels by moving the faders between buildings in the interval.) I'm thinking that we can then add more powerful lights and an extra fader pack when funds allow. Which will let us build up a nice simple 12 channel system in the slightly longer term

 

Davethsparky: Thanks for taking the time to make a second comment, I wasn't clear with my description of the cabling, I only need 20 metres in total, not 20 metres between cans.

 

Once again, thank you.

[Jamtastic3]

Hold on.... you've just got yourself a load of Par 16's? You know that these are mostly 50W fixtures???

 

What are you going to do for actual performance/stage light?

[geek3]

Yeah you might want to get some par56 or par64 and just ditch the led's