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tubs
29th of August 2005 (Mon), 08:59
I was wondering if anyone could help me sort out my colour problem. The problem is that all my images look great in Photoshop (as shot), but then all look too red in BOTH Internet Explorer and Windows Fax and Picture Viewer.

Some observations:
1. Shooting with Canon 20D.
2. Shooting in sRGB and PS working space is sRGB (sRGB IECxxx etc).
3. The image looks the same in both Internet Explorer and Windows fax and picture viewer (both are too red.)
4. Windows appears to be reading the most up-to-date colour profile, which was profiled a few months ago (Display Properties/Settings/Advanced/Color Management)
5. Profiling is with Spyder Pro. Have done it three times over two years. In the past I put the problem down to the fact I was shooting in AdobeRGB, so I don't really know when it started. I'm now shooting sRGB only to try to simplify the problem.
6. Running PSCS on a PC. Monitor is Mitsubishi Diamond Plus 93SB and video card is Radeon 9200SE.


I'm fairly sure the calibration couldn't be too far out. If I get desperate I'll hire the colorimeter again to be 100% sure, but my gut feeling is that something else is stuffing me up.

Has anybody else had this problem ?

Regards,

Chris.

gpocock
29th of August 2005 (Mon), 11:35
Hello

Not exactly the same problem But I find that different RAW processors produce different colours.

I started a thread on this at http://photography-on-the.net/forum/showthread.php?t=93140

RAitch
29th of August 2005 (Mon), 12:11
What about another computer? Perhaps you can eliminate that and maybe narrow it down to your camera.

Perhaps your saturation settings are too high or something.
Is it a red cast... or the red in your images are too high?

Oh, wait... if they look fine in PS, maybe it has something to do with how you're saving the images. Are you doing a "Save As" to JPEG... or using "Save for WEB?"

Different colour spaces would cause some colour issues... but I think normally people have the opposite problem... flat colours.
Double check both Photoshop and your camera to make absolutely sure that you're in sRGB and not aRGB for both.
Also, make sure you're not using any actions... perhaps it's changing the colour space in there somewhere without you knowing it.

tubs
31st of August 2005 (Wed), 09:57
Aaaaaarrrrrrrggghhhhh!

A weight has been lifted from my mind, for I now understand! Thanks to everybody who has helped me work this through over the past six months (!!)

Q: Why do my images look different on the Windows Picture and Fax Viewer, compared with PS ?

A: Because, contrary to the weight of advice I received (much of it from this list) the Windows Picture and Fax Viewer is NOT an ICC-aware application. - In fact, WP&FV (as does Internet Explorer) displays the image in THE DEFAULT MONITOR PROFILE.

I should have twigged when I observed that images on WP&FV look exactly the same as in Internet Explorer. I now know how to use soft-proofing in PS, and when I use the monitor profile I get exactly the same as WP&FV and IE.

I hope this information saves somebody else the anguish I went through.

Chris.

maarten1
1st of September 2005 (Thu), 17:24
Chris, I am a bit of a newbie when it comes to color profiles but I am having the same problems as you. Could you let me know how you solved this problem as my shots look much darker in windows viewer than they do in PS.

Andy Ingham
4th of September 2005 (Sun), 12:57
Chris,

I was very interested to read your posts, as I am experiencing EXACTLY the same problem. I don't really follow your findings though. Surely everything that is displayed on the PC goes through the Monitor profile defined in Windows display settings? I think you're correct in that Internet Explorer, etc., is not ICC profile aware, but my understanding is that because your images are stored in sRGB, which is the WIndows XP defaul colour space, then they would be display 'realistically' within IE. Surely you can't have to soft proof an image in PS using your monitor profile in order to know how it is going to look on your monitor?! It would then be impossible to work with images.

A link to info. about Windows XP colour space follows: http://www.microsoft.com/windowsxp/using/digitalphotography/prophoto/colorspaces.mspx

I would be very grateful to hear your thoughts on this.

Andy

lancea
5th of September 2005 (Mon), 03:49
Surely everything that is displayed on the PC goes through the Monitor profile defined in Windows display settings?
Not quite everything - which is why the arrow-cursor appears slightly blue after you calibrate the monitor for a colour temperature of 6500K. If your monitor is calibrated accurately then yes the colours will look correct in IE even though it isn't a colour managed application. You can never be sure how it will look on an uncalibrated monitor (or one that's calibrated differently to your's).

maderito
5th of September 2005 (Mon), 22:59
A: Because, contrary to the weight of advice I received (much of it from this list) the Windows Picture and Fax Viewer is NOT an ICC-aware application. - In fact, WP&FV (as does Internet Explorer) displays the image in THE DEFAULT MONITOR PROFILE.

I should have twigged when I observed that images on WP&FV look exactly the same as in Internet Explorer. I now know how to use soft-proofing in PS, and when I use the monitor profile I get exactly the same as WP&FV and IE.

I hope this information saves somebody else the anguish I went through.

Chris.
You've got it right. You didn't mention the conclusion: your monitor needs recalibration ... again.

Most monitors have color spaces that are very similar to sRGB. If the actual monitor color space is accurately characterized in its ICC profile (one of the tasks accomplished with calibration), then PS uses that information to map color accurately from any one color space (say Adobe RBB) to another (say sRGB).

As you note, when you "soft proof" against your monitor profile while in PS, you are asking PS to map the color from the image color space (sRGB in your case) to the monitor color space. Yes, that's what the image looks like outside of PS.

When you get significant differences between sRGB as viewed in PS and the same image viewed outside of PS, usually you have a monitor profile problem - or you've flubbed your color space management settings and workflow in PS.

"Significant difference" has different meanings to different observers. Since most monitors do not perfectly replicate sRGB - there should be some difference.

Most of the real world, including the web, is ICC profile unaware. So working in sRGB or converting images to sRGB is typically essential if you want to share your work with others.

lancea
6th of September 2005 (Tue), 01:54
If anyone is interested, I posted a list of some Windows applications that are and aren't colour managed. See my post of 07-22-2005 in the thread http://photography-on-the.net/forum/showthread.php?t=86654&page=2&highlight=color+managed+applications.

tubs
10th of September 2005 (Sat), 09:57
Andy,
Sorry for the late reply. I've been off work.
I understand your question and I don't yet really know why the calibration doesn't make sRGB images look ok in non-icc apps. Perhaps Maderito can help us ... ?


Woody,
I think I can learn something from you, if you wouldn't mind helping me through this. Sorry, I don't know how to 'quote' just a paragraph:

Your words - "When you get significant differences between sRGB as viewed in PS and the same image viewed outside of PS, usually you have a monitor profile problem - or you've flubbed your color space management settings and workflow in PS."

I really want to know if you're right about this. Some data:
1. I use a Spyder II Pro colorimeter (the expensive one) that is shared between the members of my local photography club. I've calibrated four times over two years and have only noticed minor changes each time. After my post about this problem I borrowed the Spyder again and during the re-cal I found I didn't need to change the settings at all.
2. I've discussed calibration methodology with other members and it seems we all do it the same way. There doesn't really seem to be any way we could be doing it wrong.
3. Perhaps most significantly, I tried this out on another club member's system and the same colour difference was present on his system.
4. To try to explain the level of colour discrepancy, the images look fine in PS, but in WP&FV (monitor profile) they are over-saturated (about 10 points oversaturated in all colours, except red, which is about 20 points oversaturated.)

I would really love to know if I'm doing anything wrong in my workflow. I now shoot in sRGB and use a working space of sRGB, so I'm not sure what I could do differently. Any comments ?

maderito
10th of September 2005 (Sat), 12:52
The purpose of monitor calibration is not to make your monitor display sRGB color space perfectly.

Your monitor will display each color primary (Red Green and Blue) in a characteristic way. The monitor profile specifies how that color representation is related to a reference standard.

For your monitor Red (255,0,0) might be (245,10,10) in the reference standard (the numbers don't matter).

Let's say you're working in PS in sRGB color space. PS is given the pixel value 255,0,0, looks at your monitor profile and translates to the reference 246,10,10 value and then to sRGB, say 240,0,0. This happens on-the-fly - i.e. in real time.

In short - a color number only has meaning when it refers to a color space (an RGB coordinate system). That color space has to be defined relatively to some universal standard.

sRGB is defined relative to a reference standard; once profiled so is your monitor; the two profiles likely differ. The info is in the ICC profiles.

What you are seeing is what I see on my monitor which is also profiled and calibrated - somewhat brighter, more saturated colors in the monitor's color space. Interestingly, we have the same monitors: Mitsubishi Diamond Pro SB930. I use GregtagMacbeth - EyeOne for calibration/profiling.

To check these issues further, create a document in PS with sRGB as your working color space. Create three patches of "pure" Red, Green, and Blue. Then proof your colors against the monitor profile: View > Proof Setup > Monitor RGB (you're monitor's profile). Then select View > Proof Colors and use Ctrl-Y to switch between sRGB and Monitor RGB. You'll probably see the red and blue brighten somewhat in the monitor profile (based on what you've said). That just proves that your monitor's color space is different than sRGB.

It would seem tempting to edit images in your monitor's color space since they'll look good to YOU. But you want your images in a color space that is universally understood - e.g. sRGB. Then each application and each user can struggle with how to represent the data on their own monitor screen or other ouput device. sRGB is the preferred space for the web since most applications are not color managed and most monitors approximate sRGB if relatively new or calibrated.

Conclusion: you're probably seeing real differences that matter only to discerning eyes. I'm assuming you're shooting in sRGB (or converting RAW to sRGB), editing in sRGB and performing no intermediate or final color conversions.

Hope this helps...

tubs
10th of September 2005 (Sat), 22:51
Thanks Woody. Yes, I'm shooting in sRGB (or in fact mostly RAW and converting to sRGB as you guessed.) I do often play with the colours, but naturally I'm comparing the *final* image in PS with the same image saved as a jpg and viewed by WP&FV.

Your very clear explanation clears up a misconception of mine (and possibly others.) Clearly, monitor calibration *doesn't* force a monitor to display in the exact sRGB colour space. Calibration simply makes sure that colours look correct in icc-aware apps. In non-icc-sware apps, even a calibrated monitor is still going to show the colours in its native colour space.

I think this will help lots of people understand this issue.

Many thanks.

Tubs.