Helpful Hints/D.I.Y.: The Importance of Color space in sharing what you want with others here and in print.

[Asher Kelman]

The subject of Color Space of digital image files arose in Erik's thread here, when it was noticed that this picture had no color space tag with it. The subsequent posts dealing discussing color space have been moved here as they constitute a an important separate topic.

Erik Jonas: Monica​

 

[Asher Kelman]

Hi Erik,

I like the colors of this picture but it appears differently in various programs as you have not tagged it with a color space. This is in an RGB type color space but it's not specified as to what exactly it is. Your pictures will show better on the web in sRGB color space. In Photoshop use Edit-Convert to color space-sRGB.

Asher

 

[ErikJonas]

...............

Rachel....Theres a number of things that could be done with it yes...But this is my art..And as it is i really like it.

Stuart the intent of this picture was not to pop...One thing with my editing is i try to treat each picture like it has its own character and i look at a picture as to what its saying to me. That will not make any sense to any of you but i'm okay with that lol...I guess i'm kind of stuck in my ways, on any image i try a number of things as far as cropping and black an white etc etc...Various contrast that kind of thing.....

Asher...Honestly and i have no problem admitting things i dont know but the bit about color space went right over my head...

Oh and Stuart no kidding about PS....I have had so many people tell me i HAVE to get PS...I'm like why and they list off all these things that i NEVER do to a image....Hey how do you do a Sephia conversion in Elements or can you? Did i spell that right? Sephia?...Anyway hows that done? and can you make the clone tool another form other then round?

One thing i dont want to do is i dont want all my pictures too look the same, i dont want a set style of shooting or editing....I try differant things and if i'm happy with it i roll with it....

But again everything everyone says gives me something to think about...And i appritiate that...

 

[Asher Kelman]

Sharing on the Web: The Importance of tagging your file with a color space!

Asher...Honestly and i have no problem admitting things i dont know but the bit about color space went right over my head...

Erik,

In simple form, not specifying the color space is like asking anyone to change the color that you have already decided is best! If there is no specification, some generic color space is used and that's like getting any old paints to touch up a precious automobile!

We assume your own monitor is color profiled. If not, one should not change the colors by eye. Never! Just use a grey card to set the white balance. Even then, the color space (think of it as the pack of crayons you used for the picture) must be recorded with your file. There's no way that the folk can see the color you expect when the color space is not specified when you save the image! All files have to be converted to sRGB before sharing them on the internet or sending them to a non-expert printer. Professionally, we use Adobe RGB for all work except on the web or unless we choose an even wider color space

What version of Adobe Elements do you have. I'll see if I can find a reference for you. Just accept my word, in the meanwhile that you do all your corrections in Adobe RGB (1998). Just set Adobe elements to that. Whenever you load a new picture into elements, have the preference set to CONVERT it, (never ASSIGN) the color space to Adobe RGB (1998). Then after all your work and you save the file as EriK_Picture_0023.PSD, in Adobe RGB color space, your archive file, then also save the file as a jpg. First convert the color space to sRGB and put it in 8BIT form. Then "Save as" as .jpg file and attach the sRGB assignment (check that option in the dialog box for saving the file).

Asher

 

[Doug Kerr]

Hi, Erik,

Asher...Honestly and i have no problem admitting things i dont know but the bit about color space went right over my head...

A color space is a specific system for representing the colors of individual pixels, often by way of three values, R, G, and B. Different color spaces differ in such matters as the three "primary chromaticities" on which they are based, the rule used to convert the three basis values to a "nonlinear" form for use in the finished digital representation, and the specific chromaticity implied when R=G=B (the so-called "white point").

Many digital cameras, by default, use a color space called "sRGB" ("standard RGB"), and as Asher has suggested, this is the preferred color space in which to encode the colors in images intended for viewing over the internet.

Another "popular" color space in the RGB family is AdobeRGB. It has the advantage that it can represent a wider gamut of colors than can sRGB. Many digital cameras will encode their output images in this color space if we set them to do so.

Typically, a digital camera will indicate in the metadata of the image the color space in which the image is encoded (the so-called "color space tag").

If we have in an image viewed in an image viewer a pixel whose RGB code is 78, 127, 239, the actual color that represents depends on which color space is involved. A sophisticated viewer will interpret the code for each pixel in the context of the color space involved, if it knows what that is, and produce the intended color on the screen. And if the image carries a color space tag, the viewer will know the applicable color space.

But if there is no color space tag, the viewer will not know exactly how to interpret a pixel code such as 78, 127, 239. It may then proceed on the assumption that the applicable color space is sRGB. If it is not, then the rendered colors will not necessarily be those intended when the image was recorded.

AS I mentioned, most modern digital cameras will tag the output JPEG image with the applicable color space (usually sRGB). If we don't do anything to interfere, an image editing program (Photoshop, etc.), when it writes the edited file, will encode the colors of the modified image in that same color space, and will tag the saved file to indicate that color space.

Evidently the images you have been posting did not have the applicable color space tag applied by the editing program.

By rights, most applications that display the image (image editors, viewers, browsers, etc.) should then assume that the color space is sRGB. But not all do.

Asher indicated that your image is treated by different applications as if it used different color spaces. That may mean that they do not use the sRGB color space as the default, which we normally expect them to do.

Best regards,

Doug

 

[ErikJonas]

.......................

Well now i'm a bit educated in that....I have to shoot in SRGB or so my understanding is for the printer where i get my prints done at.To associate the correct printer profile.I tried shooting in RGB and it would NOT let me save it with the correct printer profile....

I still get good color shooting in SRGB....

I'm off to edit more images of Monica....

 

[StuartRae]

Hi Erik,

Colour-space profiles.

I like to think (maybe not entirely accurately, but it works) of the colour-space as a triangle with R, G and B at the corners and white in the middle gradually turning into the saturated colours round the edges, like this.

If you view an aRGB image in an application that isn't colour-aware (most web browsers), the smaller sRGB template is dumped on top of the larger aRGB triangle and you lose the more saturated colours round the edges. A bit like a cookie-cutter.

If you'll forgive me for posting an image on your thread, here's an example of what might happen to an aRGB image in a typical web browser.

Regards,

Stuart

 

[Rachel Foster]

That's very helpful, Stuart. Thank you.

 

[Asher Kelman]

Color spaces: the camera, the monitor, the local drug store and the pro printer

Erik,

See how valuable your thread is! This will be an important reference for others who don't realize how pictures can be ruined at the drug store printers where they mostly have no idea of color spaces. The rule is to take the picture on the widest color space, with the most color crayons, so to speak, Adobe RGB (1988) or profoto RGB, for example. Then only when I'm giving the file to someone else or posting on the web, do I convert a copy to sRGB. That way the many more colors get re-mapped to the smaller "set of crayons" in the sRGB color space and people can see what you want them to see and no one gets confused.

However, when we print professionally, we always export the file to the inkjet printer in its original Adobe RGB (1988) or larger color space. The print software then remaps all the colors to the color space of the printer. Todays Epson, Canon and HP professional printers have magnificent color spaces and print colors way outside what is found in the limited sRGB palette. If one is sending one's best work to a commercial printer, like a Linotype Hell, which works in CMYK color space, the Adobe RGB has to be converted and again the software will do it for us.

One reason why one should be careful about severe color edits on one's monitor is that there are many living colors outside of what the LCD or CRT display can show. Even expensive RGB monitors may be missing colors seen in real life that the Epson printer, for example can readily print, true to life. So unless one is producing artistic effects, one should restrain oneself from actually altering colors beyond using a gray card or one's experience to see the color balance.

In summary, capture in Adobe RGB (1988) or Profoto RGB as 16 BIT files. That way, all the corrections made in any software program are done at the highest accuracy. Save all files in this exact form. That way, as printers improve, one always has the most rich and robust files to print on the latest printers.

Todays printers surpass in some ways the traditional color printing with wet chemicals. Things will only get better. It is sad to store files as 8 BIT sRGB files and then not be able to use the full richness of shading of light and dark and reproducing faithfully the colors you want.

"Here endeth the lesson!" Well, at least it is the end of a beginning!

Asher