low power devices for backlighting

IanWorthington said:

Hi.

I'd like to build a large back-lit frame for hanging photographs printed on transparent stock, similar to a light table.

From my readings here I'm thinking my requirements are similar to display lighting: good extended CRI and QAI numbers and a CT in the region of > 5000K. One difference would be that I do *not* want a small number of high power devices but a largish number of low power devices in order to create a diffused light source. The requirement for ventilation I'd like to avoid if at all possible.

Can anyone suggest where I might start to look for suitable devices?

Ian

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SemiMan said:

Two easy options depending on how "large" you mean:

1) If the size is tolerable, find or even buy a LED monitor and take off the screen.

2) Buy an advertising display backlight, one of the thin ones that are already assembled.

You can always change the LEDs on either to match what you want.

Other option is to just build a light box and make sure you have good diffusion.


Backlighting, CRI, etc. is not such a simple concept for photographic display. "White" will be whatever your eyes have adapted to which will be dependent on what they have been predominantly exposed to in very recently which is likely to be the room lights. If the room is lit with 3K and you use a 5K backlight, white may come across with a blue tint.

In terms of CRI, if the primary viewing is only to be backlit, then it is not about CRI, but about matching the printing to the spectrum of the bulb.

Semiman

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