Why is Kelvin color temp on digital cameras the opposite of what it is in actuality?

[waday]

Can someone convert these degrees Kelvin to Rankine for me? The US doesn't like the Metric system.

 

[WayneF]

I can't imagine why, but [°R] = [K] × 9 ⁄ 5

 

[snowbear]

I use Fahrenheit.

 

[WayneF]

Anything about color temperature or white balance in cameras uses Kelvin. Or Mired.

100 degrees K is a big change at the warm end, but is nothing at the cool end.

So the camera internals will use Mired, which is 1000000/K, which has a more consistent color shift numerically.

 

[Big Mike]

This has always baffled me: we know that low kelvin temperatures (eg 3000) look warm, and high kelvin values (eg 7000) look cool right?

So why on cameras are they reversed, and if you dial-in say 3000k the picture is made cooler?

You seem to taking it as an absolute truth that red=warm and blue= cool.

This is subjective and is primarily only used to describe artwork. It's colloquial...it's a common use of speech, but it's not formal or scientifically correct.

Color equalling a temperature, comes to us from black bodies. A black body emits electromagnetic radiation (which includes the visible light spectrum) based on it's temperature alone. So in the range of about 1000 to 10000 degrees kelvin, it goes though the spectrum of light from redish to bluish....and that is where we get 'color temperature'.

 

[chuasam]

Meh! I have a colour checker passport that I use to Colour balance in post.

 

[Alexr25]

Meh! I have a colour checker passport that I use to Colour balance in post.

So do I and as I shoot in RAW I leave the colour balance on auto and sort it out in post, but in the days of film before the instant gratification of digital photography if people were doing colour critical work with reversal film then the only way to guarantee correct colour balance was used a colour temperature meter and mired filters.
The colour temperature settings in the camera may be handy if you are shooting jpegs but for a RAW shooter colour checker passport and correction in post is the way to go.

 

[ak_]

Thanks for all the help everyone. I decided to convert all my cat pictures to sepia in the end.

 

[WayneF]

Don't cut off your nose to spite your face. Color does have considerable virtue. Learn to control white balance. There's a few ways, but a simple white card is second to none.

 

[Derrel]

The colour temperature settings referenced using The Queen's English are 704 degrees Kelvin HIGHER than the color temperature settings referenced using standard American English. A fact I just made up. Deal with it!

 

[Braineack]

So why on cameras are they reversed, and if you dial-in say 3000k the picture is made cooler?

because it's trying to adjust a yellow light to make it white.

you're telling the camera what the WHITE balance is.

if you have yellow lights and you just told the camera that they should be white, what do you expect the end result to be?

 

[Solarflare]

Can someone convert these degrees Kelvin to Rankine for me? The US doesn't like the Metric system.

1. If you dont want to use modern international units, thats quite frankly your own problem, not that of other people.

2. I can assure you any US scientist will use Kelvin. As will any serious US photographer.

Meh! I have a colour checker passport that I use to Colour balance in post.

Oh that does a lot more than just fixing light source temperature.

 

[waday]

1. If you dont want to use modern international units, thats quite frankly your own problem, not that of other people.

2. I can assure you any US scientist will use Kelvin. As will any serious US photographer.

I guess my humor was a little too dry on that one...

ETA: BTW, I'm an engineer. We use both systems, sometimes simultaneously.

 

[ak_]

This has always baffled me: we know that low kelvin temperatures (eg 3000) look warm, and high kelvin values (eg 7000) look cool right?

So why on cameras are they reversed, and if you dial-in say 3000k the picture is made cooler?

You seem to taking it as an absolute truth that red=warm and blue= cool.

Well, read the second post in this thread and you'll know I was already aware that blue is hotter than red in terms of Kelvin values. I've never had a problem controlling the white balance of any picture - just curious why it appeared reversed.

 

[Designer]

- just curious why it appeared reversed.

So what do you think now? Did one of us clear it up for you?