Chaos Corona Forum

Chaos Corona for 3ds Max => [Max] Bug Reporting => [Max] Resolved Bugs => Topic started by: Slashtore on 2017-02-24, 01:56:21

Title: When fix kelvin temp in Corona lights?!
Post by: Slashtore on 2017-02-24, 01:56:21

The selected value is not true at the moment. This problem is clearly ignored!

Title: Re: When fix kelvin temp in Corona lights?!
Post by: Dionysios.TS on 2017-02-24, 10:29:30

Quote from: Slashtore on 2017-02-24, 01:56:21

The selected value is not true at the moment. This problem is clearly ignored!

+1

Title: Re: When fix kelvin temp in Corona lights?!
Post by: jrgby on 2017-02-27, 18:01:01

Was wondering about this too. Being able to set lights up to realistic temperatures would be really useful.

Title: Re: When fix kelvin temp in Corona lights?!
Post by: maru on 2017-02-28, 17:40:04

Could someone present some comparison presenting what they are getting and what is expected? I remember similar report from some time ago, but cannot find it right now.

Title: Re: When fix kelvin temp in Corona lights?!
Post by: Slashtore on 2017-03-02, 12:29:05

Quote from: maru on 2017-02-28, 17:40:04

Could someone present some comparison presenting what they are getting and what is expected? I remember similar report from some time ago, but cannot find it right now.

That's my fault. Light sources in the corona renderer have the correct color temperature. But 6500, a white light source, can do a little light red, with some conditions. But what impact is not clear.

Title: Re: When fix kelvin temp in Corona lights?!
Post by: Ondra on 2017-03-02, 12:40:22

Reason why Corona's 6500K is not completely white:

Quote

The name D65 suggests that the correlated color temperature (CCT) should be 6500 K, while in truth it is closer to 6504 K. This discrepancy is due to the scientific community's revision of the constants in Planck's law after the definition of the illuminant.

https://en.wikipedia.org/wiki/Illuminant_D65#Why_6504_K.3F

Title: Re: When fix kelvin temp in Corona lights?!
Post by: romullus on 2017-03-02, 14:41:55

I thought you're kidding, but decided to do quick test and apparently it's true. While i can see difference in comparison mode, there's no way i could tell difference in 3,6 K when looking at pictures separately. No way :]

Title: Re: When fix kelvin temp in Corona lights?!
Post by: Ondra on 2017-03-11, 21:17:46

if this is the problem, I will close this down

Title: Re: When fix kelvin temp in Corona lights?!
Post by: dj_buckley on 2018-06-06, 23:44:26

I've actually just started a new topic without realising this one existed but I'm having the same issue.

If I have a plane light set to 6500k and White Balance set to 6500k, the result is a magenta hue on the final image.

My thread topic is here with an example https://forum.corona-renderer.com/index.php?topic=20622.0