I have long been plagued by the problem when converting AdobeRGB to sRGB. What do you guys do when you shoot in AdobeRGB and want to save a file for the web?
- When saving as it is (i.e., "save for web" in photoshop), the saturation suffers
- When converting to sRGB, the blue sky always has a cyan/yellowish cast.
Is it normal or am I doing something stupid?
photo samples can be seen here:
http://www.flickr.com/photos/37185549@N00/sets/72157594409258683/detail/
Thanks,
Tien-Chien Chen
Posted by Nat Coalson on December 7, 2006 at 10:29 AM
Tien-Chien-
1. In Photoshop, use the "Convert to Profile..." command. You can preview the conversion. Try both Perceptual and Relative Colorimetric rendering intents. Always leave Black Point Compensation on. Don't use "Preserve Color Numbers".
2. After conversion, any shifts in hue etc. can be adjusted.
3. Whether using "Save for Web..." or just "Save As...", make sure to embed the sRGB profile. Note that the NPN/RMNP recommend not to do this; it's just a file size issue. Attaching the profile will only make the file a tiny bit larger.
Note that in non-color-managed environments (your operating system dialogs and web browsers, for example) may not display files with the same color as when in Photoshop, which is color-managed.
Posted by Les Barstow on December 7, 2006 at 11:29 AM
Some programs apparently don't take well to images from the Web that have embedded profiles. For regular Web display, it is therefore best to not include the profile. If you plan on posting something for future consumption by another imaging program (PS or other), it is best to embed the profile.
If your sRGB is consistently off from your monitor display, it may be time to recalibrate your monitor.
Embedding the profile is only useful for applications that are ICC-aware. Web browsers will simply ignore it.
The real issue is that AdobeRGB is a larger space than sRGB so colors that are out of gamut will get remapped when using Relative Colorimetric intent (colors that are in gamut will not be affected in this case).
In Photoshop you can use the gamut warning feature after setting sRGB as your soft proof profile to see which colors will get remapped.
Note that sRGB is suggested as a generic profile. It doesn't mean your web browser will display it accurately. It just means that it increases the chances of most colors being more or less within gamut of most monitors (how is that for vague?).
Thanks guys for the suggestions!
What I did was ( http://www.flickr.com/photos/37185549@N00/sets/72157594409258683/detail/ )
1. convert to sRGB, Engine:Adobe(ACE), Intent:Relative Colorimetric, Use black point compensation
2. assign profile to sRGB (not sure if I need this step though)
3. save for web
I am not sure if it has anything to do with monitor calibration though, I have used different montiors to view the outcomes (see link above) and saw the same thing.
You definitely don't need to assign the profile after the conversion.
Guy
Posted by Nat Coalson on December 7, 2006 at 12:37 PM
Attaching the profile is only useful for programs that can read it. But not attaching it will cause programs that would read it to not color manage the display of the file.
Posted by Les Barstow on December 7, 2006 at 1:11 PM
Actually, regarding the monitor calibration, I was wondering if maybe you used a monitor profile during your regular workflow. I'm in the dark ages in workflow; I still use the sRGB profile as my working profile (and adjust my CRT to match using QuickGamma, until I can afford a good piece of multi-function profiling hardware). So what I see on the screen is pretty much exactly what I can expect out of an AdobeRGB->sRGB conversion. If you use a monitor profile, that isn't true; since monitors and sRGB are theoretically "close", you shouldn't see much change when doing color conversions, but if your monitor calibration is off, you will.
So if you use a monitor calibration device, it might be time to calibrate again. If not, I would suggest getting a copy of QuickGamma (Windows EXE), or going out and buying a calibration tool.
Discussion
7 replies- When saving as it is (i.e., "save for web" in photoshop), the saturation suffers
- When converting to sRGB, the blue sky always has a cyan/yellowish cast.
Is it normal or am I doing something stupid?
photo samples can be seen here:
http://www.flickr.com/photos/37185549@N00/sets/72157594409258683/detail/
Thanks,
Tien-Chien Chen
1. In Photoshop, use the "Convert to Profile..." command. You can preview the conversion. Try both Perceptual and Relative Colorimetric rendering intents. Always leave Black Point Compensation on. Don't use "Preserve Color Numbers".
2. After conversion, any shifts in hue etc. can be adjusted.
3. Whether using "Save for Web..." or just "Save As...", make sure to embed the sRGB profile. Note that the NPN/RMNP recommend not to do this; it's just a file size issue. Attaching the profile will only make the file a tiny bit larger.
Note that in non-color-managed environments (your operating system dialogs and web browsers, for example) may not display files with the same color as when in Photoshop, which is color-managed.
If your sRGB is consistently off from your monitor display, it may be time to recalibrate your monitor.
The real issue is that AdobeRGB is a larger space than sRGB so colors that are out of gamut will get remapped when using Relative Colorimetric intent (colors that are in gamut will not be affected in this case).
In Photoshop you can use the gamut warning feature after setting sRGB as your soft proof profile to see which colors will get remapped.
Note that sRGB is suggested as a generic profile. It doesn't mean your web browser will display it accurately. It just means that it increases the chances of most colors being more or less within gamut of most monitors (how is that for vague?).
Guy
What I did was ( http://www.flickr.com/photos/37185549@N00/sets/72157594409258683/detail/ )
1. convert to sRGB, Engine:Adobe(ACE), Intent:Relative Colorimetric, Use black point compensation
2. assign profile to sRGB (not sure if I need this step though)
3. save for web
I am not sure if it has anything to do with monitor calibration though, I have used different montiors to view the outcomes (see link above) and saw the same thing.
Anyway I will try these suggestions! :
Guy
So if you use a monitor calibration device, it might be time to calibrate again. If not, I would suggest getting a copy of QuickGamma (Windows EXE), or going out and buying a calibration tool.