What does the kelvin (K) mean??

Temperature above absolute zero - ice freezes at 273 degrees kelvin.

5000 kelvin means light is whiter than 3000 kelvin which is
also called warm white and is slightly yellow.

Kelvin is the numbers of degrees above absolute zero. (minus 273 degress celcius)

In regards to lamps it means the equivalent colour temperature.

Warm White - 2700k to 3000k
Cool white - 4000k

Dont know about 5000k, sounds non-standard - but must be close to true daylight.

Cheers

ThisKelvin should explain it... (Google is your friend;-))

In practical terms, a 3000K light will give a yellowish "soft" light.. generally referred to as "warm white", I believe, whereas a 5000K light is a very "white" light (commonly referred to as "cool white")....

My preference for camping is the 5000k CFL, as it seems to give more light than the 3000k (I have several of each in my kit).
At home, I prefer the softer 3000k, as the 5000k looks pretty harsh in the house.
Gerry

Think of 3000k as being close to the colour of a normal incandescent light whereas the 5000k is close to the normal fluro light.
I personally prefer a 3000k light as it's not as harsh as a 5000k light.

And just to confuse things in the case of HID lights.....the higher the Kelvin the less Lumens they put out.......ie; a 4000K HID throws out more light than a 8000K one !!!

The higher the K the whiter the light.....8 - 10000K ones will be blueish

What a fun thread. And to be really really picky, water only boils at 100 Degress C at sea level, although this varies very slightly with atmospheric pressure at any given moment.

Is there a physicist in the house? :)

Can anyone explain to me why there _is_ a minimum temperature of 0K?

Mike Harding

Dave - "how ya goin ?"....... as I recall from Trade School (a wise old ex London Uni graduate) ..... and as others have said to a point.........and in "bushman's terms" :-o) .....1. Zero degs Kelvin is as cold as anything can get ! Really cold ... in fact no plurry heat at all...nothing.... about -275 degs C I think. 2. Incandescent materials give off light when they are hot. 3. All incandescent materials give off the SAME colour of light, at the same temperature. 4. Different types of light sources rated at the same K should give light of the same colour (even if they aren't incandescent sources - its just a rating system in those cases). Hell - the foregoing could even be true !

G'Day Signman.
It doesn't really matter what you use ,as long as YOU don't use a gas bottle. LOL :-)
Cheers Bert.

As long as you lot are being picky....only water without impurities boils at 100C. Which is why your peas in water need to be slightly hotter :) And only water without impurities freezes at 0C.

did the fluoro's not fit that i gave you or are you after a different size

Member Signman
If you have to ask that questing what you need to decide is do I want 300 or 5000 moths and bugs per hour,that's reality.
Good luck
Crusher

this website explains it pretty well. http://www.schorsch.com/kbase/glossary/cct.html

It's one of the first things you learn about in photography/video production, which effects white balancing.