CHROMiX

Basic Profiles and Working Space Questions

I recently used Color Think to compare two profiles and it raised a number of issues for me. What I did was embed a custom profile I had made for my Epson 4000 Premium Luster paper/ink, inside of Adobe RGB 1998 and was surprised to see that the Epson Profile had values that were out of gamut for the Adobe profile.

At first this surprised me and caused me to realize that I didnt completely understand what all of this meant.

Does this mean that the printer is capable of rendering colors that I cant see on my monitor?

But if I choose a profile like ProPhoto as my working space would I suddenly be able to see those colors?

Does choosing the Epson profile in the Print Space box mean that it will convert the limited color numbers that I can see in my current working space to the wider gamut numbers so that they print well?

I just noticed that I could choose the Epson Profile as my working space in the Color Settings box.

Are printer profiles and working spaces the same thing?

And then on top of all of these uncertainties, I tried to find the canned Epson profile so I could compare it to the custom one and discovered that, although I can see a graphic of it using ColorSync, I cant actually drag it into the Color Think Profiles folder for comparison. It seems embedded in some hidden way.

Is there are way to use ColorSync to make this comparison or is there a way to use Color Think to do this that I havent discovered?

Answers to these perhaps simple questions would be tremendously helpful to my general understanding of color management.

Thank you,
Chris

I’ll give a couple of these a shot…

Yes. But that’s the case with just about any printer and monitor combination. One will generally clip the other somewhere, or be out of the gamut of the other.

On your monitor: Only if your monitor could physically show those colors.
On your printer: It should, as long as ProPhoto was larger than the printer color space

I think in the context of how you’re asking the question, it is.
A printer profile is a device specific profile that details how to convert colors to the software.
A working space can have that particular profile loaded, and you can work in that color space.

Here’s my monitor profile compared to one of our big VuTeks with 3M ink.
It’s quite obvious the printer can print some oranges and yellows my monitor would have a aneurysm trying to reproduce. There are also some blueish colors my monitor can’t show that the printer can actually print.
That doesn’t mean the printer can’t print the color as long as you adjust by the numbers… you just might not be able to see it on your screen in all its glory.
pixentral.com/show.php?pic=1 … VXTHz90O90

Here is a scatter plot of an image taken with my Canon 20D in RAW mode. I converted one plot to adobe 1998 from inside Camera Raw, and another to ProPhoto (I use ProPhoto) inside Camera Raw.
There’s a much broader color range to work with in ProPhoto, IMHO. I’ve compared it to a Canon 20D profile and ProPhoto will essentially capture much of the 20D’s gamut (if not all of it).
You know, It will be squashed into a smaller printer space ultimately. I suppose I go against the grain the way I go about this since most people will recommend you work in the color space that is closer to your output device.

Adobe 1998
pixentral.com/show.php?pic=1 … 3J2X43LIH1

ProPhoto
pixentral.com/show.php?pic=1 … rDTEUbcXFH

As always, if I have misinterpreted the data or your question, someone please quickly correct me. :slight_smile:

First, thank you Richard for your generous, and quick, response.

So lets see if I have this right:

Im in Tibet and use my Nikon D70 to photograph a rainbow that has colors that are vivid and inherently outside of the gamut of Adobe RGB 1998. Even though the camera only allows me to export with 1998, because the raw state is latent when I open this image in Camera Raw 3.1 those vivid numbers are still there.

But, if I choose 1998 in the Workflow Options, those color numbers are converted (and compressed) to the more limited color space and are gone forever, except in the original .nef file that, since it is read only, is tagged with 1998 but otherwise is still pristine.

If on the other hand I choose the much larger ProPhoto color space in the Camera Raw box, those original, vivid color numbers will be preserved.

But because my Photoshop Working Color Space is set to Adobe 1998 those vivid numbers will be preserved but, for the sake of display and editing, they will be converted into 1998 numbers and I will see them as less vivid renditions of the originals.

And, if I select the larger, Epson 4000 profile (color space) as my printer profile, the original vivid colors that happen to fall within THAT space will be printed. If I had gone the 1998 route from the Camera Raw stage of the process, they would not be printed.

All of this assumes that what you meant by “…as long as you adjust by the numbers”, is “…use the appropriate printer profile in the Photoshop Print with Preview box”. Is that right?

If this rendition is correctly worded, then these concepts are now within my mental gamut.

Thanks again,
Chris

Thinking this through, I just realized the flaw in my reasoning: as soon as I try to open a file tagged with a ProPhoto profile, in an Adobe 1998 working space I will get a warning of the mismatch.

Other than this, I’m assuming that every thing else is correct.

That is how I understand the way camera raw works. You are simply translating the raw data the camera sensor captured.

Your raw file shouldn’t be tagged with anything. It’s just sensor data.

They will open into a larger color space. I’m not comfortable telling you absolutely that will be the case. However, I’ve had very good luck with working in ProPhoto with my 20D.

As you clarified in your post below … you will get a warning of a mismatch.
The easiest thing is just create a custom workflow and just change your RGB working space in Photoshop to ProPhoto.

I assume the Epson 4000 color space is RGB? I’m much much more familiar with CMYK presses so I don’t feel confident to comment on this section.

Is the Epson 4000 larger at every point or only in a small point?
I’d probably still use a device independent color space even if the Epson gamut goes beyond the Adobe 1998 gamut in spots.

That’s just me assuming everything was gonna print in CMYK. I made a mistake. I thought the Epson printed from a CMYK profile. I doubt the RGB printers work so predictably along those lines … it does print from RGB profiles, right?

What I meant (even though it doesn’t apply here, probably) was even though your monitor can’t show a specific color that’s out of it’s gamut, but you know it’s inside the printer gamut, you can go in and tweak delicately adjusting by numbers in your info palette.
For example, suppose my monitor can’t accurately render 0,9,99,0 but I know my press can hit it. I just go in and adjust a section to that value and know it’s gonna print right even the monitor can’t display it correctly.

** However, I’m probably confusing things as my little mind always converts into CMYK. **

I’d rather someone with experience printing from RGB help you with this.
God, I sure hope I understood your original questions… :slight_smile:

I would greatly welcome any other voices of advice with these questions but your repsonses have been extremely helpful. I even understood the points you were making about CYMK conversions.

Thanks a lot.

And yes, the Epson printer does work from RGB profiles. It uses CYMK inks but I’m assuming that either the Adobe, Mac or Espon print driver routinely makes that conversion.

Thanks again,
Chris

Chris,

If you’re looking for a good introduction to CM, download the free PDF on PSCS2 colour management by Martin Evening on http://www.photoshopforphotographers.com/pscs2/downloads.htm.

Martin’s series of books ‘Adobe Photoshop X for photographers’ (where X = lots of different versions :-)) was where I started to get an idea of what CM was really about. IMO it’s not a beginner’s book on PS, but it’s recommended nevertheless.

I suppose the key things about CM to understand initially are
(a) a set of numbers describing colours in an image only have a meaning if you know the space those numbers occupy;
(b) a profile is a useful tool that can be used either to describe the characteristics of a device (e.g. a particular printer), or to define an artificial colour space (e.g. Adobe RGB (1998));
© by ‘tagging’ an image with a profile you can define the space the image occupies;
(d) when converting colours from one colour space to another, this usually involves (behind the scenes if you’re using Photoshop) an intermediate space, usually Lab, for which the terminology is ‘profile connection space’.

If it helps, think about (a) in terms of temperature: if I tell you the temperature is 32, then unless you know whether I mean Celsius or Fahrenheit, you don’t know whether it’s hot or cold. For (d) it might help to think about a (slightly artificial) way of converting between foreign currencies - to convert from currency X to currency Y, first convert X to US Dollars then convert from US Dollars to Y. This is very crude analogy as it doesn’t address the issue of gamut, but it helps some people.

Also, Steve Upton’s essay ‘the color of toast’ is a classic explanation of what device characterisation/profiling is all about. It’s on the Chromix web site somewhere.

HTH

Alan

Here’s a great article I should have referenced you to earlier…
outbackphoto.com/color_manag … essay.html

Some extracts from the article

One other not-so-small issue with ProPhoto RGB is this:

Other resources to help you decide if you would benefit from ProPhoto RGB:
luminous-landscape.com/tutor … -rgb.shtml
naturephotographers.net/arti … 203-1.html

What some say is while the Adobe 1998 gamut is 100 percent efficient, the ProPhoto gamut encompasses colors we can neither print nor see. However, I’m personally sticking with ProPhoto RGB.

Thanks to both Alan and Richard for the advise and links. Slowly but surely all of the essential theoretical and practical aspects of CM are constellating in my mind.

Now all I really need to know is what does IMHO stand for?? "It Might Help Out?

Thanks again,
Chris

IMHO = In my humble opinion
YMMV = Your mileage may vary

Those are the only two I know so I tend to use them to death.

Hah!

Thanks,
Chris

There’s a good write-up in this thread, as well.

[Do digicams "see" in sRGB/AdobeRGB/ProPhotoRGB/ or)

For ‘IMHO’, and more acronyms and smileys than you can shake a stick at, see http://www.netlingo.com/

HTH

Alan

Bit late to this thread.
Chris, with all the procedures described RAW-16bit Prophoto into Photoshop the final tweaks can be donr via
View-Proof setup and the custom profile for your paper/ink/printer combination.
When printing always set the printer preview Options-Printer Profile to the custom profile.
Also memory plays tricks with how remember colours.

You do need an accurate quality monitor to get a good soft proof.
Hope it helps.
Malcolm

I am new to CM, and would like to compare aRGB with ProPhotoRGB using ColorThink. Profile Manager does not list ProPhotoRGB anywhere. Yet aRGB and sRGB are present, and I can access ProPhotoRGB in ACR.

How did aRGB and sRGB profiles arrive in my comptuer and how does PS know of ProPhotoRGB?

Mac DP G5, 10.4.6

Thanks,

Sonny Taylor

Go into your Library -> Application Support -> Adobe -> Color -> Profiles -> Recommended

On the way you should run across them. They’ll probably be waiting for you in the ‘Profiles’ or ‘Recommended’ folder.