Lighting a hall: theatre spots of halogen floods?

I'm trying to acquire lighting for a school hall. The space is vaguely circular (actually an irregular pentagon!) c. 14m diameter. It is used for school plays and concerts where approximately half the 'circle' is occupied by performers, the other half by the audience. I want to provide good lighting over the performers without blinding them or light spilling too much onto the audience. The lights have to be fixed at the perimeter of the hall about 3m up.
Budget is approximately 50p ;-)
Bargain basement approach would be 400W halogen floodlights fitted with 300W lamps controlled by domestic 400W rated dimmer switches. But I've seen tome spots on eBay and wondering about them: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item )0844636345
Presumably proper spots will have better defined lighting angle, as well as being able to take coloured filters if we wanted. However the seller doesn't know whether the beam angle is adjustable on these and they'd be a chocolate teapot if they had fixed narrow beams. Anybody familiar with these beasts who can say? Comments on general spots v floods choice welcome.
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John Stumbles

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On 6 Jul 2013 10:22:57 GMT, John Stumbles wrote:

h

New bubbles needed at £15 a pop...
These days I'd be looking at LED par type stuff. 1/10th or less power consumption and colour variable (via DMX) without have to get the steps out and shove bits of gell in front of them. CPC have a range from £30 to >£100, might be worth seeing what Maplin have in store s o you can play as well (having noted the prices at CPC)...
With a 3 m ceiling height any light source is going to be a quite a shallow angle so a bit "in the eyes". There might be too much spill from the common sort of parcan luminair for them to be placed at the rear of the audience. No chance of a scaffold bar (ali...) at 2 to 3m back from the front of stage over the audience area?
I'm not at all clued up on DMX but I think you'd just need a single mains feed looped between each lamp and similary the DMX cable (twin screened). The lamps ought to have loop through for the DMX and you give each one a seperate address via DIP switches.
The low power of LED means the whole lot (unless you have a stupid number of them, like > 50) can be run of a single 13 A socket without having to worry about loading on the socket or ring. OK a ring should be able to support 24 odd 300 W lamps but what else is on that ring? The tea urn... Oh and *much* less heat being pushed into the space as well.
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Dave.
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Dave Liquorice wrote:

I'd not be wanting to go for standard incandescent lighting nowadays. The bulbs for the ones you link to aren't cheap, from what I remember. They also last dozens of hours, not thousands. I'd also suggest that for 300W halogens, the dimmers be rated at 1000W`or so to account for surges. Domestic dimmers might also have reliability problems with the control knobs.
These:-
http://www.jpleisure.co.uk/item1185.htm?gclid=CLO_j-PymrgCFXMdtAodRRoAog
Will need feeding replacement bulbs every few hundred hours of operation at a tenner a time.

+1, and I'd also be speaking to my local DJ supply shop. They may have some gear in from a local DJ who's upgraded recently, and they'll certainly have some halfway decent stuff that can take quite a bit of mistreatment.
The extra initial cost of LED lighting will repay itself in bulbs and energy costs over not too long a time.
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Tciao for Now!

John.
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On 06/07/2013 13:49, John Williamson wrote:

We got new ones for our village hall from Thomann last year and they will also do autonomous sound to light for discos as a bonus. In an ideal world you also want a basic DMX control desk and cabling as well (and teach a few people how to use it or you will never be free!!!).
You don't need to buy filters since they are RGBY output (OK you might need a diffuser on the front to mix it up a little). Brightest are
http://www.thomann.de/gb/stairville_led_par_64_cx_3_rgbw_18x8w_s.htm
The cheapest half decent ones are about £100 each.
http://www.thomann.de/gb/stairville_led_par_64_cx1_rgbw_15x3w.htm
They tend to be cheaper than buying in the UK if you don't mind them coming with continental plug on. Not a big DIY job to install. You pay more initially but use a lot less electricity in the longer term.
If anyone knows where to get them cheaper I am interested!
You can get dimmer previous generation ones much cheaper second hand but I think they would be a poor investment. Installation is once and for all with a bit of control wiring and not much waste heat generated.
BTW Your intended budget is perhaps 3 orders of magnitude too low.
You might get away with repurposing suitably chosen domestic kitchen spotlamps for a basic white light only setup.
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Regards,
Martin Brown
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On Sat, 06 Jul 2013 13:11:58 +0100, Dave Liquorice wrote:

Slightly less, but ballpark.

I know. But 50p budget :-(

Nope. Not without access kit I haven't got & haven't got time and/or money to get ...
---8<---

Will mostly be needed in winter so not an issue.
Guess maybe we should go with halo floods for now, drum up a budget for proper kit one day (SEP: my sprog won't be at the school much longer so I won't be involved)
thanks Dave
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John Stumbles

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John Stumbles wrote:

Try the Blue Room forum if you haven't already come across it.
Owain
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snipped-for-privacy@gowanhill.com wrote in

You may run into probnlems with the capacity of the circuit it you fit a number of tungsten lights. (Ah - memories flooding back of a 3kW dimmer and watching it glow - hoping it could cope!)
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