[joshvm]

RGB should be fine, especially if you use a genuine ultra-high CRI source. A few companies make them, I think Waveform is one of the more well-known. If you really want to spend money, the optics suppliers like ThorLabs sell broadband LED sources. In an ideal world you could calibrate the image sensor against a known spectrum so you'd know its response. If you can estimate colour to a reasonable degree then you can transform it to what it "should" look like. Nevermind that pixels are single-wavelength as well.

https://store.waveformlighting.com/collections/led-strips/pr...

Negative Supply use something similar in their light tables, though I don't know exactly what the source or spectrum is. They're highly regarded enough that I think it's not an issue.

You can also use LEDs for enlarging, but you need to be careful about buying the right bands for the paper. I've used Luxeon SunPlus with some success as you can buy the correct green/blue for the different contrast layers. Though for B&W, even a random 5500K module from Cree worked quite well.