Am 16.06.2012 11:58, schrieb clipka:
> Am 16.06.2012 11:24, schrieb Ive:
>> Am 15.06.2012 19:48, schrieb clipka:
>>> Am 15.06.2012 17:14, schrieb Warp:
>>>> Le_Forgeron<jgr### [at] freefr> wrote:
>>>>> If the sky is "blue", why do you see a yellow sun ?
>>>>
>>>> The sun is not yellow. It's white.
>>>
>>> That depends on the color space.
>>>
>>> In sRGB (whitepoint = D65 = ~6500K), the sun is a pale yellow.
>>>
>>> In Wide Gamut RGB (Whitepoint = D50 = ~5000K), the sun is actually a
>>> pale blue.
>>>
>>> If you use a color space with the equal-energy point (E) as whitepoint,
>>> the sun is even a pale green.
>>
>> This makes actually not much sense as all RGB-color-spaces are device
>> dependent. So when you use e.g. WideGamut RGB or Adobe RGB as a
>> *viewing* color space with a sRGB device you are obviously doing
>> something very wrong.
>
> You should know better

I do ;)

> (or I'm misunderstanding you).

So lets try to clarify.

> sRGB is not a device-dependent color space.
> WideGamut RGB is not a device-dependent color space.
> Adobe RGB is not a device-dependent color space.

As I translate "not device-dependent" into "device-intependent" those 3 
statements are plain wrong.

Again: all RGB-color-spaces are device-dependent because they are 
defined by chromaticity primaries, whitepoint and transfer function.
None of them is able to express all possible colors - or better all 
colors an average human can see and distinguish.
You might have been confused as e.g. WideGamut is usually only used (and 
called) as an intermediate working color space but such *working* color 
spaces are also called virtual color devices.
On the other side there are device-intependent color spaces like CIE xyz 
or L*a*b and it's derived Lch color space. Those are indeed able to to 
express all possible colors.

At least this is the terminology I've learned long ago.

As a side-note, Microsoft is in favor of using scRGB and - by allowing 
for negative color component values - making this also a 
device-independent color space and as far I can tell from the beta it 
seems this is even a build-in Windows 8 feature.


> My EIZO S2402W's color space is device-dependent, yes.
>
> The panel of an individual EIZO CG245W has its own device-dependent
> color space, but the EIZO CG245W as a finished product can be calibrated
> to various different standard or non-standard color profiles (with some
> limitations imposed by the panel's gamut of course).
>

I own only the CG243W and its own gamut is large enough for Adobe RGB.
Viewing some neon-style images there is really fun.
The problem when using such a wider gamut is that color banding becomes 
also much more obvious. Therefor I did recently (after being tired of 
walking around in Skyrim) replace my gaming-graphics-card with something 
serious that allows for 10bit output via display-port and the EIZO panel 
is also able to reproduce 10bit without interpolation.
And - quite to my surprise - this actually works.

> There are device-dependent color spaces, and there are
> device-independent color spaces. The standard color spaces are,
> obviously, device-independent.

Well, see above, you've got the definition of device-independent wrong.


-Ive

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