Question on color profiles... - Page 2

Gymrat76 · 25th March 2005

Originally Posted by Zerstorer

"Preserved Colour Numbers" essentially shows you what you would see in a program that either doesn't recognize profiles or that the profile is not applied.

Basically, this hints that your system monitor profile might not even be working.

Are you using an Eye-one? If so you should see the desktop change colour just when the profile loads itself during windows startup.

It doesn't really matter, any colourspace can be selected as your working space as long as the gamut it wide enough to satisfy your needs.

Yes, I'm using Eye 1, and I do see a color change when my desktops loads up, so I know the calibrated profile is working. So you're saying the fact that I can see a difference in color when I check the 'preserved color numbers' points to a problem with my calibrated profile?

Zerstorer · 25th March 2005

I think I've found the problem, apparently IE(and all other PC browsers) don't recognize profiles at all. sRGB was adopted as a internet standard because it was reasonably close to the output gamut of most monitors, but no PC browser in existence has any form of colour management, hence all it does is direct translation of values.

The colour variation you see is due to IE taking the raw RGB values and representing it through the monitor profile. In the case when your moniter profile's gamut closely matches sRGB, it will look more or less identical. However, it appears that there is a significant difference in your case. (To confirm this, mail me your moniter profile and I can render a gamut comparison to see if its the case.) zerstorer@fastmail.fm

What Jopel is showing you is how to proof the image, showing how it appears on a target output device that doesn't have colour management.

You would then see how the image would look like in IE to YOU.

However, I wouldn't recommend adjusting it such that the image would appear as you want it in IE. This is because, everyone else on viewing your image on the web would have a different monitor profile active, thus it would still be interpreted differently. Just stick to the common sRGB standard and leave it so that everyone will at least have a similar reference point.

Currently if they were to download your image and view in on their PC in a colour managed software, they would probably see the same colours as you do in PS-CS, so you needn't worry.

Right now, probably the only people who can view your web images exactly as they do in PS-CS are Mac users running Safari or Internet Explorer which are currently the only browsers with colour management.

Zerstorer · 25th March 2005

Here are the Gamut plots:

sRGB vs Gymrat's Moniter

You can see that the gamut of his moniter greatly differs from the sRGB standard. Hence, sRGB images would have a certain degree of deviation when viewed on such a monitor without colour management.

sRGB vs Sony G420
Here, you see a 4 year old Sony G420 plotted against the sRGB standard. Notice that the gamut shape and reach is relatively close, which shows a better match to sRGB.

Basically, this shows the limitations of sRGB as a standard. It's only meant as a painless convenient way to represent and share images on the web, without colour managed applications. sRGB is arbitarily defined from the gamut of the ITU-R BT.709 HDTV phosphor set.

For strict accuracy in viewing images, one still needs to use a colour managed software which will remap the rgb values to give a perceptually similar result.

Last comparison just FYI:

Gymrat76 · 27th March 2005

Thanks for the help guys, I've learned a lot

arrsoo · 28th March 2005

Quote:

For strict accuracy in viewing images, one still needs to use a colour managed software which will remap the rgb values to give a perceptually similar result.

Zerstorer,

can you give some example of colour managed software?? I am still very confused even at the adobe gamma monitor calibration stage! So confused till I don't know how to ask for help

Zerstorer · 29th March 2005

Originally Posted by arrsoo

Zerstorer,

can you give some example of colour managed software?? I am still very confused even at the adobe gamma monitor calibration stage! So confused till I don't know how to ask for help

Programs with colour management support are Nikonview, Acdsee 7, Photoshop CS, Photo Mechanic....etc.

These programs will correctly identify the profiles tagged with images and translate them to your moniter profile.(if any)

Adobe gamma can give you a decent moniter profile provided that you follow the instructions properly and are able to discern colour and tonal hues accurately.

For best results, while using the adobe gamma utility, goto the following page and adjust the gamma while viewing the gamma test pattern there instead. It gives a more precise result IMO.

http://www.normankoren.com/makingfineprints1A.html

The above link is also helpful in explaining all the concepts involved.

However, such visual calibration is generally limited to midtone gamma and colour neutrality as you are unable to adjust the individual colour gamma curves directly. A hardware calibrator will give you better neutrality in highlights and shadows.

arrsoo · 29th March 2005

zerstorer,

thanks for the link, looks like digestions time again

quekky · 30th March 2005

Zerstorer, what software do u use to do those Gamut plots? looks interesting

quekky · 30th March 2005

now i'm confused with the profiling and color management. i just tried opening a file (saved as sRGB jpg) on several programs and all give me different colors

(click for 100%)
(from left to right) IE, PS no proof, ps w/proof, opera, NC, acdsee

so which picture is suppose to be the accurate color? they all looks different color to me. as u can see, i have set my monitor, acdsee and ps(w/proof) to the same monitor profile. this profile is calibrated by eye1. especially ps(w/proof) looks very out of place

Zerstorer · 7th April 2005

I'm using Chromix Colourthink for the gamut plots.

Trust your PS, Nikon Capture and Acdsee 7. Any differences are just due to the conversion engine used; They are basically the same for all functional purposes. Opera and IE don't do colour management at all.

Your setting for PS w/proof option doesn't make sense. PS uses your monitor profile by default. When u use the softproof with "preserve colour numbers" checked you are simulating an output without colour management, that's why the output for this looks like your IE output. Remember that "soft proofing" is a simulation, the program tries to simulate what you would get, it isn't 100% accurate but its pretty close.

quekky · 7th April 2005

strangely my NC have a slightly more greener tone compared to PS (no proof), if u take a look at my printscreen carefully

Gymrat76 · 16th April 2005

Thanks to all who contributed. I did the best thing and sent my photos for printing, without color correction. Thankfully the colours all look like what I see on Photoshop!

Thanks for a good lesson on color profiles!

25th March 2005	#23
Zerstorer Senior Member Join Date: Jul 2002 Posts: 3,610	Here are the Gamut plots: sRGB vs Gymrat's Moniter You can see that the gamut of his moniter greatly differs from the sRGB standard. Hence, sRGB images would have a certain degree of deviation when viewed on such a monitor without colour management. sRGB vs Sony G420 Here, you see a 4 year old Sony G420 plotted against the sRGB standard. Notice that the gamut shape and reach is relatively close, which shows a better match to sRGB. Basically, this shows the limitations of sRGB as a standard. It's only meant as a painless convenient way to represent and share images on the web, without colour managed applications. sRGB is arbitarily defined from the gamut of the ITU-R BT.709 HDTV phosphor set. For strict accuracy in viewing images, one still needs to use a colour managed software which will remap the rgb values to give a perceptually similar result. Last comparison just FYI: Last edited by Zerstorer; 25th March 2005 at 08:34 PM.

30th March 2005	#29
quekky Senior Member Join Date: Sep 2003 Location: www.irphotography.com Posts: 1,380	now i'm confused with the profiling and color management. i just tried opening a file (saved as sRGB jpg) on several programs and all give me different colors (click for 100%) (from left to right) IE, PS no proof, ps w/proof, opera, NC, acdsee so which picture is suppose to be the accurate color? they all looks different color to me. as u can see, i have set my monitor, acdsee and ps(w/proof) to the same monitor profile. this profile is calibrated by eye1. especially ps(w/proof) looks very out of place Last edited by quekky; 30th March 2005 at 09:48 PM.

7th April 2005	#30
Zerstorer Senior Member Join Date: Jul 2002 Posts: 3,610	I'm using Chromix Colourthink for the gamut plots. Trust your PS, Nikon Capture and Acdsee 7. Any differences are just due to the conversion engine used; They are basically the same for all functional purposes. Opera and IE don't do colour management at all. Your setting for PS w/proof option doesn't make sense. PS uses your monitor profile by default. When u use the softproof with "preserve colour numbers" checked you are simulating an output without colour management, that's why the output for this looks like your IE output. Remember that "soft proofing" is a simulation, the program tries to simulate what you would get, it isn't 100% accurate but its pretty close. Last edited by Zerstorer; 7th April 2005 at 08:13 PM. Reason: Grammar corrections

27th March 2005	#24
Gymrat76 Senior Member Join Date: May 2004 Posts: 1,591	Thanks for the help guys, I've learned a lot

29th March 2005	#27
arrsoo Member Join Date: Sep 2004 Posts: 63	zerstorer, thanks for the link, looks like digestions time again

16th April 2005	#32
Gymrat76 Senior Member Join Date: May 2004 Posts: 1,591	Thanks to all who contributed. I did the best thing and sent my photos for printing, without color correction. Thankfully the colours all look like what I see on Photoshop! Thanks for a good lesson on color profiles!