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mitternacht
01-30-2004, 05:01 PM
Hi all,

I've had a problem ever since joining this site. Some photos look excellent in my editor (Corel Photo-paint, CPP) but due to different color management get strange colors in internet explorer (IE). They are usually colder and especially orange and warm red tends to be a little purpleish in IE.

I am sure IE is capable of showing the same colors as CPP. So I wonder, does anyone know if I can configure CPP to use the same color management as IE so that when I edit photos for the internet I can work with them the way they will look like in IE.

Other members of the site will probably see my pictures totally different anyway since different screens show things differently, so it's not a major issue, but if anyone knows anything about this it would be nice to know.

Thank you

Simon

AdrianW
01-30-2004, 05:47 PM
Trouble is IE doesn't support embedded ICC profiles as far as I can tell. The only way to get your pictures to display in IE/Mozilla roughly as they do on screen is to disable your profiles in CPP. Not optimal, but it works!

Use the RGB values to determine colour shift - if your greys show as RGB 128,128,128 you're fine, if they show as 200,128,128 you have a red shift. Also use the histogram function if you have such available - if you have a normally exposed average type scene you should just see one or two pixels at each end :-)

torben
01-30-2004, 06:35 PM
I'm certainly no expert on color-management, but as far as I understand, the default color-space on PCs is sRGB. If you are editing in another colorspace that contains more colors - like fx. adobeRGB - some change in color is to be expected when the image is displayed on a sRGB device. I don't know if Corel Photo Paint can convert an image from one color-space to another, that would be the preferable solution. Turning color-management off probably means that sRGB are used as color-space.

mitternacht
01-30-2004, 06:45 PM
Thank you Adrian and Torben for your answers. I will try turning color management off.

Adrian: I have seen the histogram function and tried to change its parameters to see how it works but never figured it out. Can you explain it?

AdrianW
01-30-2004, 07:44 PM
Usually the histogram options shows you a graph, x-axis (across the bottom) shows the intensity from dark (left hand side) to bright (right hand side). The y-axis (up/down) shows the number of pixels counted of that brightness.

A graph with everything bunched up to the left usually means your image is underexposed, everything to the right means over exposed. If there's a strong bump in the middle and nothing at either end you probably need to increase the contrast :-)

Does that help?

mitternacht
01-30-2004, 08:44 PM
Yes, that helps. Thank you.

I thought it was something like that when I took another look after posting. I should have figured that out earlier, I study spectrum histograms almost every day at the university... I major in physics.

What I really wondered was if I could use this to manipulate my picture, but if I understand you right it's just an analytical tool.

AdrianW
01-30-2004, 11:17 PM
Well, the problem is I'm not familiar with CPP so I can't say what you can do in CPP - in Photoshop the Levels command allows you to make simple adjustments to the histogram using a couple of sliders. I have no idea whether the Histogram tool in CPP does that or not...

The histogram is most useful for initial analysis and to determine whether you've made any errors in your processing :-)