CShake escribió:
> Alain wrote:
>> Blackbody(3200) is rather redish, not slightly off-white, similar to a 
>> spotlight running with a much lower voltage than it's rating.
>> A value around 4500 to 5000 would give you a much yellower tint. And 
>> around 6500 will be close to white. 7000 will give a marked blue cast.
>>
> The reason I'm using a low temperature blackbody is that the lamp I'm 
> trying to simulate (the HPL740 used in ETC brand source four lights) is 
> at that temperature, and most other stage light instruments (except arc 
> lamps) are around 3200K. The color gels I'm simulating were made for use 
> with this temperature light, so for most light sources there is also a 
> thin object with a color filter value in front of it.

   Remember you can always change the color system white point to something 
more like an indoor film. Here are some examples from the Lightsys demos:

// Change color system white point for lights
//CIE_ColorSystemWhitepoint(My_ColSys, Illuminant_A)    // tungsten 2856K
//CIE_ColorSystemWhitepoint(My_ColSys, Blackbody2Whitepoint(3200)) // Film 
tungsten A
CIE_ColorSystemWhitepoint(My_ColSys, Blackbody2Whitepoint(3400)) // Film 
tungsten B

   I think a 3400K white point should make the 3200K light to look slight 
yellowish.

   Regards,

--
Jaime

Post a reply to this message