Marginally related to the subject -- how about the color of LED lights.

As I recall, when LED microlightss first appeared they were mainly available in colors. It was only later that reasonable-quality white LEDs were offered.

The colored LEDs were marketed as being good for preserving night vision, and I bought into that after experiencing it myself.

HowEver...

Now that I have a widely adjustable intensity on my Photon Freedoms, I find myself less likely to pick an LED for its night-vision properites.

In fact, I think I'll just stick to white Photon Freedoms from here on out.

Bear