On 1 Oct, 13:46, "dennis@home" wrote:
"Adam Aglionby" wrote in message

...



On 1 Oct, 10:07, "Mungo \"Two Sheds\" Toadfoot"
wrote:
Mungo "Two Sheds" Toadfoot wrote:

Are they A Good Thing for cheering up a kitchen through the winter,
and possibly having a beneficial effect on the symptoms of SAD? I'm
having some bother finding a 6' one locally but if they're worth
having I'll continue the search.

Si

And... is there any difference between 'normal' daylight tubes and 'full
spectrum' jobs?

added sci.engr.lighting as crosspost from uk.d.i.y

Probably several multiples of price.....

Full Spectrum is marketing mumbo, fluro by the very way it works has a
peak and trough spectral power distribution.
People like the dodgy Dr Ott sell all sorts of impressively packaged
"full spectrum" fluorescent lamps, if you really want full spectrum,
halogen has a continuous spectral output.

Daylight tubes are often just high colour temperature, which in an
internal kitchen might look very cold and as Andrew said can have poor
actual colour rendering. High colour rendering index lamp is really
more what you want, decent lamps made by big manufacturers aimed at
things like the print, textile and car refinishing business be more
appropriate.

Some research says colour does make a difference, been some research
on use of blue LED in resetting circadian rythmns in the elderley,
some research says intensity matters some that time and length of
exposure is most important, doesn`t seem to be a well understood
phenomenon.Offering opportunity for snake oil salesman to enter the
fray.

Probably BS though as sunlight is not blue and its lack of sunlight that
causes SAD.

Cant place the link offhand but it was serious research, blue LED
because its a very efficient generator of blue light aginst tungsten
or even fluro. Sunlight contains a lot of both visible and increasing
amounts invisible blueviolet radiation....

I would use warm white tubes myself and you need plenty of them, one tube is
not what you usually see to treat SAD, maybe five tubes or a 250w metal
halide lamp?

Intensity dosen`t seem to be universally accepted as the main
factor ,though personally think it is probably one factor.

Adam




Adam