Joseph Holmes Ekta Space P5

[Rich14]

And then there's this. Looks very interesting:

http://www.xs4all.nl/~tindeman/raw/curve_tools.html

"CurveTools: LuminanceCurve & LightnessCurve

This is unlike other common tools, such as Photoshop's standard curves or a lightness curve in Lab mode, both of which have side-effects on saturation and sometimes hue."

Rich

[QT Luong]

About two weeks ago, I emailed Joe to ask him if there were colors actually captured that are in Prophoto but not Ektaspace. He was graceful enough to give me a very quick and detailed answer. Since he was still working on the new spaces, he asked me to hold on reposting that answer. Now that he is done (http://www.josephholmes.com/profiles.html) here it is.

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From Joe Holmes

Thanks for inquiring. As it happens, I have recently completed a new series of five RGB working spaces for use with digital captures, in a wide progression of gamut volumes: DCam 1, DCam 2, DCam 3, DCam 4 and DCam 5. The first is the smallest and the last is the largest. 2, 3 and 4 are general-purpose spaces. 4 is very similar to ProPhoto in gamut (very very large). 5 is bigger still and just barely includes all visible colors but is overly large for general use. 2 is 25 percent larger in Lab gamut volume than Adobe RGB, but much better shaped, so it can hold about 50 percent more useful color range than Adobe RGB. DCam 3 is in between, and somewhat larger than Ekta Space, plus differently shaped.

The DCam spaces have more on the red to greeen (yellows) side, mainly, and their shape and color range was very, very carefully considered only after a great deal of research into which colors in the world around us wind up where after various common RAW processing methods.

And I have new and much improved chroma variant sets for all seven of my spaces. Plus I have chroma variant sets for ProPhoto and Adobe RGB. So whatever suits you, I've pretty much got it now. I will be announcing all this on my web site as soon as I finish the automation necessary to make online selling of the sets feasible. Also, once anyone has purchased one set at the normal price, they will be entitled to purchase any of the other sets for their own use at a $35 discount. In most cases the normal price is $95, but for the Adobe RGB and Pro Photo sets it will be $85.

It is unfortunate that Camera RAW 3 and Canon's DPP v.2 both are closed to profiles for both the source (camera) and output (working space), and only let us use the built-in profiles. Many RAW converters are open, however. At this point, my favorite converter is RAW Developer by Brian Griffith, at http://www.iridientdigital.com, version 1.5.1 or later. It's exceedingly clever and has lots of great features, as well as being completely open.

All of my working spaces share the same superior tone curve except for Ekta Space PS 5, which uses a gamma 2.2 tone curve, like Adobe RGB. If you have files in Ekta Space (as indeed you do), you can open up the deep shadows nicely by <assigning> Chrome Space 100, an updated version of my original Ektachrome Space profile, which is otherwise identical to Ekta Space (just a different tone curve). So in your position it's often ideal to have both the Ekta Space PS 5 and the Chrome Space 100 profile sets, each w. 29 chroma variants.

That way, on an image-by-image basis you can decide to open up the shadows quite a bit, and you can adjust the chroma in either condition (w. either tone curve in place).

And you can decide if you want to jump to one of my better designed digital camera working spaces or stick with one of the two main industry standards, and there is a variant set for any of those. Pro Photo's design is a good one, except for the tone curve, though it will only make a very small difference in the quality of your printed work to use my DCam 4 with its more perceptually linear tone curve (more printable levels when converting into an 8-bit per channel printer of decent linearity in its raw state, i.e. as profiled).


Anyway, once I get my site pages up, I won't have to try in vain to explain all of these details in emails. It's a long story, too long to tell completely this way. But you can get the idea. For most people, I recommend DCam 3 as the best general-purpose digital capture RGB working space. It's big enough to hold, for example, neon reds. And just about 100% of all flower or brilliant artificial fabric colors. A few flower highlights will still be clipped that will clip less with one of the larger two DCam spaces (4 or 5), but those spaces have more room by far than any printer or display for those lighter colors, so it's not necessarily beneficial to have that extra room. It's sort of a clip now or clip later deal, when you are converting from the RAW file.

It's time for bed, past actually, so let me know if I can help with more details tomorrow, Saturday.

DCam 2 is intended to be a super-efficient, conservatively sized space that nevertheless holds just about all common colors. DCam 1 it a super small space, somewhat smaller than sRGB, but intended for use only with pictures that have fairly neutral highlights and no very saturated colors, in order to minimize quantization error with them to a great extent (a subtle, quality-protecting method), and not for general use.


Thanks again,

Joe Holmes

Kensington, California

http://www.josephholmes.com