6500k white

[lasse1309]

Hello Guys,

had some discussion here about corona white balance being at 6500k default - while vray and "real" cameras have it at 5500k.

I am pretty sure there is an idea behind setting it at 6500.. if anybody knows more about this, hints are well appreciated (and honoured :))

lasse

[Ondra]

6500K is the color balance of sRGB color space which is the de-facto computer standard for images. BTW Corona white balance is "relative" - 6500 means "no change, outputs mapped 1:1 on inputs"

[Ludvik Koutny]

Yep, to put it in practical context, 6500 is there so that if you have a texture, where certain pixel when measured in photoshop has say RGB 210,80,20, and you map this texture to self illuminated or emissive plane with multiplier of 1.0 and you do not touch exposure, if you measure same place of the map on the output render, it will still remain RGB 210,80,20. So by default, your colors are not modified in any way.

If default was 5500k, then imagine what a chaos it would make if you would make white wall material, yet it would render light blue under neutral light conditions :)

[lasse1309]

guys, thanks a lot for your answer - appreciate that a lot.

well, for me it made sense a lot, the guy sitting on the other side of the table was confusing me with things like "but in vray..." "...noooo white is 5500k" :D

well, and there "white" is 5500k .. i am with you, because the sRGB standard was the value i was "kind of" aware and what i found in my google search.
hm.

i will confuse him back while talking to him in °C. so white is around 6227°, hrhr ;)

cheers

[Juraj]

Where did your colleague found that 5500 is White in Vray ?

My default exposure is D65, as in average daylight and D55 is correctly slight greeenish filter. But white would be just white.

Corona's relative approach to base photographic controls instead on sRGB standard is confusing (but only photographing purists might object, or those who require to precisely match footage), although logical solution. Since it doesn't have full tint counter balance, it's useless to use anyway, this is what Post-production is for now.