Untagged better than sRGB for PC viewing?

[saynomore]

Hi, this probably is a bit off-topic, but I guess people here are more enlightened on ICM than on other forums by necessity.

Since most monitors' color space is usually bigger than sRGB (or in the worst case, just different), shouldn't it be more reasonable to leave the file untagged, and let the pic spread its colors over the monitor's color space? Now, if the monitor is not calibrated, this would show of course different colors, but sRGB files also will. So I really don't see the advantage of using sRGB for web and such.

What I am not sure also is if untagged files will look the same in calibrated monitors. I think so, given that I use dual monitors in my setup, both calibrated, and both show radically different colors before calibration kicks in at startup, and after that, all pics, even the wallpapers show the same color.

Am I missing something?

 

[Estragon]

I have been trying converting my sRGB images to Adobe RGB in Elements and there is a difference on screen - the images have much more punch. Funnily, the difference doesn't show up if I view the images outside elements (in a browser say) so I am not sure if Elements is just trying to represent the wider colour space on screen or if it actually manages to achieve this. I have only started doing this recently, so I don't yet fully understand the implications, but reds in particular have much more punch.

 

[Dominic.Chan]

What I am not sure also is if untagged files will look the same in
calibrated monitors. I think so, given that I use dual monitors in
my setup, both calibrated, and both show radically different colors
before calibration kicks in at startup, and after that, all pics,
even the wallpapers show the same color.

If you have two monitors on the same system that are properly calibrated (and matching in gamma and luminance), all images will look similar on both monitors, regardless of whether they are tagged or not.

The problem with untagged images is that there is no unique way of interpreting the colour information. If I use two scanners to scan the same picture without using colour management, they can look very different. With proper colour management (or sRGB), they should look very similar.

 

[saynomore]

If you just assing an adobe RGB tag to a sRGB file, then you will see the image more saturated, but if you do a conversion (the proper thing to do) then the changes will be more subtle, you will see changes only where sRGB's gamut is smaller, like deep green/blue colors.

Just assigning a tag will not change the RGB values of the file, it will just tell the program how to read those values. So while your file looks more saturated, it is inaccurate. Converting will change the RGB values to the equivalent in that color space you are converting to. You will only notice a change from ARGB to sRGB when you have these saturated colors in your picture, and that is not always the case.

These pics were both converted from raw into prophoto (a bigger color space) and then as last steps, converted each into Adobe RGB and sRGB. You can see the difference in the green/blues of the right upper corner, and some minor difference in the saturated pink, but not any discernable difference in the skin tones, nor in the yellow. But this is also limited to your monitor's color space, so you will only see the difference in the colors that your monitor can display.

DOWNLOAD these pics (right-click - save image as) and open them in a color-aware application like EOS viewer, zoombrowser, breezebrowser, photoshop (you'll probably get a warning, just conserve the files' color spaces), ACDsee, etc.

Windows picture and fax viewer and RAW viewer are NOT color aware last time I checked. If you see them in a non-color aware app, like probably the browser you are using right now, the sRGB will look more saturated, but it's just because the app does not read ARGB nor SRGB, just that the sRGB values are closer to "normal" on a monitor.

Adobe RGB:



sRGB:

I have been trying converting my sRGB images to Adobe RGB in
Elements and there is a difference on screen - the images have much
more punch. Funnily, the difference doesn't show up if I view the
images outside elements (in a browser say) so I am not sure if
Elements is just trying to represent the wider colour space on
screen or if it actually manages to achieve this. I have only
started doing this recently, so I don't yet fully understand the
implications, but reds in particular have much more punch.

 

[saynomore]

Thanks, what about 2 calibrated monitors on different systems? I would guess untagged files also look the same (given the match in luminance too).

Anyway, after some testing I think I get it now...

Thanks again.

If you have two monitors on the same system that are properly
calibrated (and matching in gamma and luminance), all images will
look similar on both monitors, regardless of whether they are
tagged or not.

The problem with untagged images is that there is no unique way of
interpreting the colour information. If I use two scanners to scan
the same picture without using colour management, they can look
very different. With proper colour management (or sRGB), they
should look very similar.

 

[Dominic.Chan]

Thanks, what about 2 calibrated monitors on different systems? I
would guess untagged files also look the same (given the match in
luminance too).

On different systems they may look different, e.g., if they have different gamma settings (1.8 vs 2.2).

 

[saynomore]

Freakin' explorer won't let you save the original pics, so Either use Firefox and save them or here are the links...

Adobe RGB:

http://pg.photos.yahoo.com/ph/ao9news/detail_hires?.dir=ea49&.dnm=8cef.jpg

sRGB:

http://pg.photos.yahoo.com/ph/ao9news/detail_hires?.dir=ea49&.dnm=7728.jpg

 

[Dominic.Chan]

If you just assing an adobe RGB tag to a sRGB file, then you will
see the image more saturated, but if you do a conversion (the
proper thing to do) then the changes will be more subtle, you will
see changes only where sRGB's gamut is smaller, like deep
green/blue colors.

Since Estragon was converting in the opposite direction (from sRGB to Adobe RGB), there should be no visible changes at all from the conversion.

BTW, can you send me the original RAW image? I find this image works well to demonstrate the differences in gamut.

Thanks.
Dominic Chan

 

[saynomore]

As you can see, those are bits from different parts of the RAW pictures. I did this photo shoot for a family, and then after that I realized all of the kids dressed similarly, but in radically different colors.

I'll do a similar TIFF, though. Just let me know what color space you want it in. I can do a 16-bit in prophoto.

If you just assing an adobe RGB tag to a sRGB file, then you will
see the image more saturated, but if you do a conversion (the
proper thing to do) then the changes will be more subtle, you will
see changes only where sRGB's gamut is smaller, like deep
green/blue colors.

Since Estragon was converting in the opposite direction (from sRGB
to Adobe RGB), there should be no visible changes at all from the
conversion.

BTW, can you send me the original RAW image? I find this image
works well to demonstrate the differences in gamut.

Thanks.
Dominic Chan

 

[Estragon]

You are right, I am assigning, not converting. Thanks for the clarification. Back to the drawing board!