I am getting too old to understand color profiles!

(I did a search, then got lost in the results )

When using the Digital professional software, I am thankful to choose between three conversion settings: sRGB, Adobe RGB & Wide Gamut.
I then get lost. I know I want to use ARGB on my camera for the wider gamut, but, I don't know whether the benefit is worth the extra work, in comparison with just shooting @ sRGB...
It's sort of scary when I open an ARGB pic, to see how dull and dead it looks, yet 'supposedly' it is much better.

Could someone please better explain this (at least better than the manual)

Thanks

There is so much bad information floating around the photography boards when it comes to color management. If you really want to understand it without wading through a bunch of wrong info, buy a good book. I can recommend Color Confidence by Tim Grey.

Now the full answer to your question is very long, so I will just give you some advice. If your Adobe RGB pictures look dull when you open them, it means that you haven't opened them in a color managed application with a working space set to Adobe RGB. If you are primarily viewing your images on your monitor and making prints at wal mart, costco, etc. or you're having prints made by ofoto, shutterfly, etc use sRGB. These printers all expect images to come to them in sRGB. If you intend to make fine art prints at home with a high quality ink jet printer or at a lab that works with various color spaces, learn about color management and what Adobe RGB has to offer.

Finally, let me just say that you can get outstanding results with sRGB. There are times when the larger gamut of Adobe RGB will give better results, but believe it or not, there are times when sRGB's smaller gamut will give better results.

Thanks for your reply.

I was going to read up on this one day once i am used to my new printer.
But i too have been drowned in info.
I can't even remember what my 300d has as it's default setting.

Oh well-my printed photo's look pretty damn awsome-i guess i never will have to learn it all 8) 8)

Here's an article you may find helpful.

Regards,

There's probably not much point in worrying about choices between sRGB and Adobe RGB if you aren't using a calibrated monitor and custom (or even canned) profiles for your printer/ink/paper combination, however, if you want to go this way, Adobe RGB will give you significantly more saturated greens than sRGB . As far as I can seen, that's the principal difference, plus a whole lot of additional subtle shades of pale cyan and similar that are possible as a result of the more saturated green.

If you are using a recent edition of PS, you can demonstrate this fact for yourself by creating pure red, green and blue squares (255,0,0 etc) with a brush, and checking how the CMYK percentages change on the 'info' palette as you assign different profiles.

I use the ProPhoto colour space available in PS CS because it produces better yellows than Adobe RGB. As far as I can see, ARGB is incapable of generating a pure yellow on the print. It's always contaminated with a small percentage of Cyan, eg. 97%Y + 9%C. ProPhoto is 100%Y.

CMYK is not one, universal color space. Most of us use the default CMYK of Adobe PS - so called SWOP. When looking at the "Info" palette in PS, you are looking at on-the-fly conversion from your working RGB and the working SWOP CMYK space. Strictly speaking, there is no such thing as "pure" yellow. There is only 100% yellow for a given color space definition.

You can judge how well a given color is produced in an RGB space by inspecting CMYK values. But if you're using CMYK as your reference, you would have to have a real good feel for how colors in a specific CYMK color space actually look when printed.

For more, see: http://www.creativepro​.com/story/feature/193​47.html

Woody,
What you write might well be theoretically correct, however there's no substitute for practical, empirical evidence. By 'pure yellow' I mean the yellow of the ink in your yellow cartridge and/or (R=255 + G = 255) on the monitor. The 'purest', most saturated yellow you can get is when an RGB yellow (255,255,0) on the monitor is translated to 100% yellow ink on the papaer. (I know theoretically there are imaginary colours that are saturated beyond the capability of human perception, and also dyes and inks that are more saturated than the ones you may be using in your printer. But those are separate issues).

If you are working in the Adobe RGB colour space, it's impossible to get the printer to print 'pure' (ie. 100%) yellow as a separate, discrete colour. It's noticeably tainted with cyan, ie. it's a slightly greenish yellow. This fact can be graphically demonstrated by breaking open a spent cartridge and spilling or thinly painting the yellow ink on whatever paper you use. If you then print out the most saturated yellow you can create in PS (255,255,0) from the ARGB colour space and compare it with the yellow ink you painted on the same type of paper, you will see what I'm talking about. The Adobe RGB yellow is slightly green by comparison. Printing the same yellow that's been asigned the ProPhoto colour space produces a yellow that's the same as the pure yellow ink that was painted.

What's more, the on-the-fly conversions from RGB to CMYK that the info palette shows, reflect these differences, ie. 255,255,0 = 97% yellow + 9% Cyan for ARGB and 100% yellow only, for ProPhoto. The percentages might or might not be completely accurate, but they seem about right.

A similar situation arises when comparing fully saturated Green (0,255,0)from sRGB and Adobe RGB. The sRGB green is quite dramatically yellower than the ARGB green on the print, but this is obvious only when camparing the two colours side by side. Again, the on-the-fly conversions to CMYK reflect these observations, ie. 0,255,0 in sRGB = 63% Cyan + 100% Yellow. 0,255,0 in ARGB = 97% Cyan + 100% Yellow.

Another dramatic example; if one selects from the Swatches the colour described as 'pure Cyan', you will find that in sRGB, 0,174,239 converts to Cyan 69% + Magenta 14%. In Adobe RGB the same 0,174,239 converts to Cyan 92% + Magenta 3%.

The above are just a few practical examples of the differences between colour spaces. In many situations these differences might be irrelevant. If the image doesn't contain any truly saturated Cyans or Greens, for example, or shades that are dependent on those saturated colours as a component, the differences between sRGB and ARGB in the print would not be noticed.

On the other hand, Mother Nature can provide some very saturated colours; the greens of leguminous plants that manufacture their own nitrogen; a freshly fertilised lawn or the myriad of brightly coloured flowers, many of which might have colours well outside the gamut of sRGB.

By the way, in case any of this is confusing, I'm not referring to any conversion from an RGB colour space to a CMYK colour space such as SWOP. As far as I understand, the printer software does its own conversion and assigns a particular combination of CMYK percentages for each RGB value it is presented with, and that combination will depend I guess (I'm no authority on this) on the colour space of the source image and the printer/paper/ink profile that's being used.

I've assumed the CMYK percentages on the right side of the info palette are giving at least an indication of what those CMYK equivalents are in respect of the different colour spaces. I could be wrong, though .

My point is simple: RGB and CMYK color numbers are only interpretable with reference to the associated color space.

Like RGB color spaces (sRGB, ARGB, etc) CMYK spaces come in many flavors (SWOP, Sheetfed, etc.). The default CMYK space in Photoshop is SWOP, but can be changed in Color Settings.

I’m not saying anything more or less.

Take your example of "pure" yellow for which you are using CMYK as a reference, i.e. Yellow = 100%

First – recognize that in most RGB spaces with R=G=255, B=0 (yellow), CMYK devices cannot produce this color. The Photoshop color picker shows that these RGB values, when converted to CMYK colors numbers, are out of gamut (designated with an exclamation point - ! ). If you actually convert the RGB yellow to its closest equivalent CMYK (via Image>Mode>Convert to Profile), you get a visibly less saturated yellow.

Second – take the other side of your example:

Start in CMYK (SWOP) space and create the color Y=100%, C=M=K=0%.
Now look at this color numbers for this "pure" CMYK yellow in ProPhoto RGB (PRGB), ARGB and sRGB:

PRGB: R=255, G=238, B=75
ARGB: R=255, G=241, B=45
sRGB: R=255, G=242, B=0

Each color space assigns different coordinates to the CMYK yellow. But it's the same color, and would be defined as such in an appropriate reference color space (e.g. LAB). The different amount of Blue in the above example doesn't change the color appearance. The color looks the same if viewed within its assigned color space.

Perhaps this is obvious. I thought my point was fairly straightforward.

Woody,
You're right. The CMYK numbers do change if one changes the CMYK profile in Color Settings. I guess the reason SWOP is the Photoshop default is because it most closely resembles the way most printers' software interprets the RGB numbers. And of course, all the fully saturated RGB combinations appear to be out of gamut, which is not to say, however, that the numbers do not still provide an approximate indication of the precentages of inks that are laid down by the printer.

Whatever the numbers, the facts are, as I've observed them, ProPhoto fully saturated yellow (out of gamut or not) is yellower than Adobe RGB yellow, and Adobe RGB green is greener than fully saturated sRGB green.

Actually, playing around with these numbers leads me to believe that modern inkjet printers/papers have a much wider gamut than the default SWOP CMYK. For example, CMYK green from the swatches is 100% Cyan + 100% Y on the info palette. Painted on the monitor it becomes RGB 0,166,81. In sRGB working space, this translates to SWOP C=83, M=6, Y=96, K=1, all in gamut. Assign Adobe RGB to this green and the SWOP numbers become C=100! + Y=100!, out of gamut.

Unfortunately, I haven't got any printer/paper profiles on this computer I'm writing from, but I find it difficult to believe 0,166,81 in the Adobe RGB working space would print out of gamut on an Epson 1290 with Premium Glossy, say.