Kelvin vs lumen????

[Corax]

Hey Suba Dudes,

Got what is possibly a dumb question, but when you go to buy a headlight globe it usually states the globes kelvin output ( ie 4500k ). Why is this more important than the luman input? I thought that kelvin was a way of measuring heat while luman measured how much light is given off. Surely in this case light output is more important than heat output. Or have I got the whole thing wrong? Thanks in advance for clearing this up.

Cheers,
Corax.

[Mr Top Hat]

Hey Suba Dudes,

Got what is possibly a dumb question, but when you go to buy a headlight globe it usually states the globes kelvin output ( ie 4500k ). Why is this more important than the luman input? I thought that kelvin was a way of measuring heat while luman measured how much light is given off. Surely in this case light output is more important than heat output. Or have I got the whole thing wrong? Thanks in advance for clearing this up.

Cheers,
Corax.

im pretty sure kelvin is for colour not heat so like those cars with HID's there colour is somthing like 6000K which is why they look kind of blue.
most halogen bulbs are close to 3000k

and lumen is light output. both of these things are important when choosing a light bulb

hope this helps

[Jimmy G]

The "Kelvin" relates, in this case, to colour temperature - there is very good Wiki on it : http://en.wikipedia.org/wiki/Color_temperature

[AlpineRaven]

I tend to find lower number of kelvins ie. 4000k a better light output than higher kelvins.
Cheers
AP

[wrxer]

agreed, kelvin is the frequency of light output and lumen is the brightness. 1 lumen is 1 candleworth of light. as ap says, the lights with the best penetration are the 4000k ones, the 6000k are bright but dont penetrate well and the 3000k ones are golden yellow and not the best either, they reckon the 3000k ones get better over time but i pulled mine as the 4000k ones were best