Building Light Boxes/screens

[Jules007 0]

Hi all. I am about to build some new light boxes (i know, you either love em or hate em) for the front of my rig. Always used a black cloth but after looking at some recent photos it needs something to lift the front as most of the light comes from the top.

 

I am proposing using some 25w harlequin bulbs (which CPC have on offer at the mo) and gonna make them approx 1'x3' with a UV name board in between (i know a bit old hat!!!!, but i like it!!). Chipboard/Ply or MDF?? I am also gonna use Elvcon's rather than the older Bulgins.

 

I have built some in the past but that was many years ago and just wondered if there was any advice or pitfalls i should look out for????

[bluejools 0]

if you have already built some then you are probably a couple of steps ahead.

 

i would think about

 

stability - front of show always a potential impact point

depth - if you are still using real bulbs they kick out heat - keep the perspex far enough away

protection - protect your corners and edges - clip together for transport.

 

last lot I built - many many moons ago I used marine ply. Very stable structure - can take the knocks, the damp - a pint etc.

[McCardle 1]

I'd also be concerned about the long term availability of filament lamps. Every year the Energy Saving Trust has banned the sale of a type of filament lamp, starting with the 100W bulb, closely followed by the 60w lamp and this time around its the 40w which will be removed from sale. I reckon this is the reason why CPC are selling off their stock in a sale, I think its later this year when we wave goodbye to the 25W version, no doubt next year the 15W will be the last to go, completing the 'ban'.

 

So, technically, you are building a new system using a soon to be obsolete component.

 

I used three lightscreens several years ago, and it was a nightmare keeping on top of the bulb changes. The filament in a 15w / 25w bulb is extremely thin and fragile, and the knocks and bumps encountered in Mobile work, as well as road vibration during transporting was enough to fail a bulb long before the end of its useful life. For this reason, if you do still go down this route, make sure you stock up on plenty of spare lamps, because (a) you'll probably need them and (b) In a year or so, they may be no longer for sale

 

 

[Jules007 0]

Thanks for the advice. The end of the filament light bulb is indeed nigh, but at some point i would guess they may make replacements using LEDs (hopefully), if not someone should look into it!!! I also hope that at some point they replace the A1/259 projector bulbs with an LED version. The extra cost for these would be offset by the life of the bulbs.

[McCardle 1]

I also hope that at some point they replace the A1/259 projector bulbs with an LED version. The extra cost for these would be offset by the life of the bulbs.

 

The original A1/259 has a lumen light output of 3600, so I suspect it may be a long time before LED technology catches up with those levels of output. Given that the LED Lighting industry is still struggling to reproduce a decent quality alternative to replace the GU10 reflector lamps used within the domestic household environment, and they are only around 500 lumens.

 

 

The closest to the 24v 250w lamps at the moment are the LED floodlights available which replace the 150w and 300w halogen outdoor floodlights, unfortunately the led 'chip' used within these is far too large to fit the footprint of a A1/259 lamp. The heatsink and price tag for these 30w and 60w LED's are also huge too .

 

 

I think the LED and indeed any 'green' energy based lighting industry is the most overhyped and exagerated industry in the UK (apart from perhaps Electric vehicles!). I bought a £18 Cree LED lamp which was supposed to directly replace a conventional halogen lamp of 1600 lumens, yet it also stated in small print on the box that it produced only 750 lumens. How a 750 lumen device can be sold as directly and like for like replacing a 1600 lumen one shows just how misleading the industry is. However put 'green energy' or 'energy saving' against these products claims and you can basically get away with selling or claiming anything :wall:

 

 

I must admit that I bought some LED lighting effects and they are dwarfed by and look completely lost when used alongside conventional effects using A1/259's and Disharge lamps.

 

That said, I can buy A1/259's for around £2.40 each, assuming an LED version comes out which costs £90 (the cost of the aforementioned LED floodlight), thats a hell of a lot of bulb changes to justify the price tag of the LED version, i'd probably be long retired before it had paid for itself in bulb change savings.

 

but at some point i would guess they may make replacements using LEDs (hopefully), if not someone should look into it!!!

 

I doubt that there is the demand for coloured lamps to justify the R&D costs, apart from perhaps the orange and red lamps used in Grannies' flame effect electric fire!. A lot of lighting which traditionally used to use coloured bulbs (Xmas lights, Tree Lights, lights around the outside of pubs etc) has long since evolved to begin using LED based duralight and ropelights.

Edited January 25, 2013 by McCardle