[time-nuts] [OT] Ikea Lamp

[Steve Rooke]

Not wishing to push this O/T thread more O/T but coming from England,
and now in New Zealand, we have these sodium streetlights which I
think are a pain in the neck. They have only two narrow spectra of
yellow light and although they produce light it makes it hard, if not
impossible, to make out colours. I wonder if they are being used in
other members countries?

Steve

2010/1/31 Dave Martindale <dave.martindale at gmail.com>:
> If you care about accurate colour rendering, stick with incandescent,
> preferably halogen.  "White" LEDs are actually blue LEDs coated with a
> phosphor that absorbs some of the blue light and emits approximately yellow
> instead.  If you look at the spectrum, you'll see a broad yellow peak and a
> narrower blue peak.  Your eyes see it as approximately white, but it's
> deficient in red and green compared to a black body emitter like hot
> tungsten.  On the other hand, it's not as spiky as the output of
> fluorescents.

-- 
Steve Rooke - ZL3TUV & G8KVD
A man with one clock knows what time it is;
A man with two clocks is never quite sure.