What affordable lights should I use for a number of large, very bright light-boxes?

Question

I'm working on printing a number of large, very bright backlit prints.

I need lots of lights that are affordable since I'll be needing quite a number of 'em.

My other concern is color reproduction, so I need light sources with a CRI of 100 preferably. Any suggestions?

Answer

You're only going to get 100% CRI out of tungsten lights or special purpose fluorescent tubes. The tubes are going to be expensive, not to buy but to install seeing as you need special fittings with transformers, starters and chokes. You might be able to get a bulk discount on fittings designed for office buildings however the tubes are likely to be long to fit behind a print in any case.

The best you will get out of a CFL (compact fluorescent lamp) is about 90, though I've heard talk of higher. That may be good enough for you, it would certainly be cheap to run but the bulbs aren't cheap.

The final option is daylight balanced tungsten bulbs which will give you 100 CRI, will be cheap to buy if you can find them. Which country are you based in? The EU is quickly making it illegal to sell tungsten bulbs but you can still find them in quantity with some retailers (at least this was the case last time I looked). This option will be most expensive to run, however.

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