POV-Ray : Newsgroups : povray.binaries.animations : CIELCHuv D65 gamut sphere : Re: CIELCHuv D65 gamut sphere Server Time
26 Feb 2024 01:58:37 EST (-0500)
  Re: CIELCHuv D65 gamut sphere  
From: Mike Horvath
Date: 25 Mar 2017 11:08:52
Message: <58d68804@news.povray.org>
On 3/25/2017 9:46 AM, clipka wrote:
> Am 25.03.2017 um 12:22 schrieb Mike Horvath:
>> On 3/25/2017 5:21 AM, clipka wrote:
>>> Am 25.03.2017 um 09:19 schrieb Mike Horvath:
>>>> The visible gamut under D65 illumination mapped to spherical CIELCHuv
>>>> coordinates.
>>>
>>> You seem to be interpreting L as a polar coordinate, which is rather
>>> unconventional -- and as a matter of fact doesn't make much sense, since
>>> it causes all grey tones to collapse into the center.
>>>
>>> The official CIE LCh colout space is cylindrical in nature, not
>>> spherical (though the visible gamut under D65 might take on a somewhat
>>> spherical shape).
>>>
>>
>> Yes, I know. Adding a bit to the beginning of the radius creates a hole
>> that keeps the gray values from collapsing.
>
> Why use this non-canonical representation of CIE LCh/Luv in the first place?
>

Back when I was learning how to use paint programs, before I learned 
what a color solid was, I came up with a spherical representation of the 
HSL color model (see attachment). I always liked the shape, and it stuck 
with me.


Mike


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Attachments:
Download 'hsl_sphere_color_solid.fs.png' (419 KB)

Preview of image 'hsl_sphere_color_solid.fs.png'
hsl_sphere_color_solid.fs.png


 

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