attention color whizes: non-typical sRGB/RGB/ProPhoto question

[jeremypayne]

Now lets move on.

Sincerely,

Joofa

I can't move on until you tell me what a color is!

[Graystar]

I can't move on until you tell me what a color is!

How can he tell you what he doesn't know?

[digitaldog]

In ColorThink Pro Adobe RGB (1998) has a reported Gamut volume of 1,207,520. Adobe RGB with a D50 WP (JoofaRGB) has a reported Gamut volume of 1,224,250.

My comment is so what.

Note that these calculations don’t have any way (nor need) to specify a rendering intent.

Neither have a gamut volume close to ProPhoto RGB but I suspect everyone here from post #1 realizes this.

[jeremypayne]

How can he tell you what he doesn't know?

I'm getting that impression ...

It is an important point.  To say a "color" is not in a color space without being able or willing to define it ... is ... just pure sophistry.

[joofa]

Neither have a gamut volume close to ProPhoto RGB but I suspect everyone here from post #1 realizes this.

That was never the issue.

Joofa

[joofa]

Adobe RGB with a D50 WP (JoofaRGB) 

Please think carefully, as this JoofaRGB is the space you have been seeing in all the gamut tools that you have mentioned! I informed you of that multiple times.

Joofa

[digitaldog]

That was never the issue.

It wasn’t after you cleaned up this language:

It does not seem like that Prophoto RGB is always wider than Adobe RGB

[joofa]

I can't move on until you tell me what a color is!

What do you think a color is?

[digitaldog]

Please think carefully, as this JoofaRGB is the space you have been seeing in all the gamut tools that you have mentioned! I informed you of that multiple times.

That was never an issue. At least once we got past the idea that Adobe RGB (1998) is Adobe RGB (1998) based on its three unique and specified units that define that color space! That was after more language munging on your part.

[joofa]

It wasn’t after you cleaned up this language:

It was pointed out to you from the very start. Please see below:

Digitaldog,
I am not claiming that the volume of Adobe RGB is bigger than Propphoto RGB. Just that Adobe RGB does not seem to be fully contained in Prophoto, while still apparently being smaller than ProPhoto RGB in volume.
Joofa

Sincerely,

Joofa

[joofa]

That was never an issue. At least once we got past the idea that Adobe RGB (1998) is Adobe RGB (1998) based on its three unique and specified units that define that color space! That was after more language munging on your part.

What are those 3 unique and specified units?

Joofa

[jeremypayne]

What do you think a color is?

That's not the point ... YOU are making the claims about colors ... I'm trying to interpret them.

If you cannot (or will not) define YOUR terms ... this is simply an exercise is sophist mathsterbation.

[MarkM]

I've made an AdobeRGB profile in Photoshop adapted to D50 based Br. Lindblooms adapted values.
This is slightly larger than the regular D65 profile.
I just don't know whether or not Photoshop is the appropriate tool ...

I've thought about what one would do to make a joofaspace profile—I'm curious about what you put into the profile you made. The Adobe98 profile that I have already uses the D50-adapted primaries. What primaries did you use in the home-made version? Do they both have same primaries?

My .icc profile which I assume is standard has: R[.610, .311, .019] G[.205, .626, .061] B[.149, .063, .745]

[digitaldog]

It was pointed out to you from the very start. Please see below:
Joofa

Again you are wrong and using sloppy language. From the start? The post I quoted that you made (#5) was dated December 31, 2010, 09:25:44 AM. Now you bring this up, 3 days later (and god knows how many posts):

Quote from: joofa on January 02, 2011, 11:20:06 AM
Digitaldog,
I am not claiming that the volume of Adobe RGB is bigger than Propphoto RGB. Just that Adobe RGB does not seem to be fully contained in Prophoto, while still apparently being smaller than ProPhoto RGB in volume.
Joofa

The main issue so many of us have with you is you don’t genuinely seem to be making an effort to communicate very well. Either totally disregarding questions or providing proof of concept, or just being insulting. Your argument would be easier to accept, well at least analyzed if you wrote more clearly and stopped moving the goal posts during the game!

We’ve gone from you initially saying: It does not seem like that Prophoto RGB is always wider than Adobe RGB. We have to assume you are talking about the gamut here, not someone’s hips!
Then you move onto bastardizing Adobe RGB (1998)’s native white point taking us into another direction.
Then we finally see its not so much bastardizing as ignoring how the WP’s map with these profiles in every application known to man and dog (unless can tell us otherwise, a question still not addressed after frequent requests).

What are those 3 unique and specified units?

Primaries, WP and TRC Gamma. I told you about this way back when, using Photoshop’s Custom RGB Working space dialog to see this and alter it.

[joofa]

Digital Dog,

I don't think we are moving forward. Unless you make an attempt I am not going to reply to "running in a circle" situation. I can only take a horse to water but not make it drink. I think I have made enough arguments to support what I have said. Those who understood it got it.

The argument is now becoming counter productive. If I see a post from somebody that needs my clarification then I will step in. Otherwise, have a nice time and enjoy the ride.

Sincerely,

Joofa

[digitaldog]

Digital Dog,
I don't think we are moving forward.

Based on your history of writings here, I so agree! Its interesting to note how like so many of the posts here, when you are shown a record of your activity and actions towards others, you just want to take your toys out of the sandbox and go home. Its telling.

[tho_mas]

I've thought about what one would do to make a joofaspace profile—I'm curious about what you put into the profile you made. The Adobe98 profile that I have already uses the D50-adapted primaries. What primaries did you use in the home-made version? Do they both have same primaries?
My .icc profile which I assume is standard has: R[.610, .311, .019] G[.205, .626, .061] B[.149, .063, .745]

Well, these are the primaries adapted to D50 by BL:
R 0.648431    0.330856    0.311114    G 0.230154    0.701572    0.625662    B 0.155886    0.066044    0.063224
(see: http://brucelindbloom.com/WorkingSpaceInfo.html#AdaptedPrimaries )
In Photoshop's tool you can only use x and y but not Y. Therefore struck through above.
This is why I am not sure whether the profile is correct.
But as it matches the regular AdobeRGB profile in the grapher above (relcol) and also matches an Adobe-RGB-spectrum converted (relcol) to ProPhoto (see attachment) ... I would guess it's okay. At least okay for comparision purposes... as a profile it is probably not useable as it lacks too many profile tags (it's obviosuly the most rudimentary form of a profile).
Attached also the primaries of AdobeRGB 1998 and adapted to D50 in Photoshops tool.

edit: the slight difference in gamut volume here: http://www.luminous-landscape.com/forum/index.php?action=dlattach;topic=49940.0;attach=35571;image ...
is obviously due to the rounded numbers to four decimal places.

[MarkM]

Thanks tho_mas,

I've never played with the custom profile setting in photoshop. It's interesting that it wants chromaticity coordinates instead of XYZ coordinates. Thanks for posting the image.

[tho_mas]

It's interesting that it wants chromaticity coordinates instead of XYZ coordinates.

aren't these automatically calculated based on the chromacity values offset with the white point?

seems so... Color Think provides the XYZ coordinates of the profile ...

[MarkM]

aren't these automatically calculated based on the chromacity values offset with the white point?

That's not my understanding. Chromaticity coordinates are a 2D projection from the 3D XYZ space onto the unit triangle. They are not dependent on the white point.

The calculation normally given is:

x = X/(X+Y+Z)
y = Y/(X+Y+Z)
z = Z/(X+Y+Z)

(The CIE loved the letters x y and z for some reason)

This guarantees that x + y + z = 1 which makes one of the variables dependent on the other two. e.i. if you don't know z you can calculate it from x and y: z = 1-x-y So z is normally ignored.

You can take an ZYX coordinate like the blue primary: 0.1881852, 0.0752741, 0.9911085
and from it calculate the chromaticity coordinate: 0.0600 0.790 (rounded).

Edit:
I didn't see the images you uploaded. I'm not sure how PS goes about calculating the XYZ coordinates the colorthink shows. I would be interested to know.