Author Topic: Color difference in preview at 100%  (Read 2990 times)

Offline tgray

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Color difference in preview at 100%
« on: January 23, 2009, 10:31:21 AM »
When I open up an image, in this case a scan from a minilab with an embedded SRGB icc profile, in the preview pane, the color differs from what is show in the contact sheet (less saturated).  To further confuse me, when I zoom into a 100% of the image, the color changes and matches that of the contact sheet.  At magnifications greater than 100%, the color is the same as the 100%; it is only at zooms lower than 100% that there is a difference. 

From what I've seen, at views less than 100% while previewing, the color is less saturated.  This happens if color management is on or off. 

Any ideas?

Offline Kirk Baker

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Re: Color difference in preview at 100%
« Reply #1 on: January 23, 2009, 11:12:14 AM »
When I open up an image, in this case a scan from a minilab with an embedded SRGB icc profile, in the preview pane, the color differs from what is show in the contact sheet (less saturated).  To further confuse me, when I zoom into a 100% of the image, the color changes and matches that of the contact sheet.  At magnifications greater than 100%, the color is the same as the 100%; it is only at zooms lower than 100% that there is a difference. 

From what I've seen, at views less than 100% while previewing, the color is less saturated.  This happens if color management is on or off. 

While it would help to know what file type you're working with, I'll take a guess and say the the image likely has two images in it, one being a fairly high-resolution thumbnail and the other the full image data.  It sounds like one of the two images isn't really in the color space of the embedded ICC profile.

-Kirk

Offline tgray

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Re: Color difference in preview at 100%
« Reply #2 on: January 23, 2009, 11:17:33 AM »
Hmm.  Just a 1000x1500 jpg from a minilab.  I've done nothing to the file in terms of editing other than adding some metadata. 

Offline Kirk Baker

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Re: Color difference in preview at 100%
« Reply #3 on: January 23, 2009, 11:19:33 AM »
Hmm.  Just a 1000x1500 jpg from a minilab.  I've done nothing to the file in terms of editing other than adding some metadata. 

Well if you want to share it with us we can take a look at it.  Please click on my name to the left of this message, then click on the 'personal message' link.  I will respond with upload instructions.

-Kirk

Offline Kirk Baker

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Re: Color difference in preview at 100%
« Reply #4 on: January 23, 2009, 12:25:02 PM »
Hmm.  Just a 1000x1500 jpg from a minilab.  I've done nothing to the file in terms of editing other than adding some metadata. 

Well if you want to share it with us we can take a look at it.  Please click on my name to the left of this message, then click on the 'personal message' link.  I will respond with upload instructions.

I got your sample image.  It looks the same at all sizes to me in both the Preview window and Contact Sheet window with color management turned on.  I am running on a Mac with the as yet unreleased Photo Mechanic 4.6.

What version of PM are you using, and what OS are you running?  Has your monitor been color calibrated recently?

-Kirk

Offline tgray

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Re: Color difference in preview at 100%
« Reply #5 on: January 23, 2009, 12:36:03 PM »
Version 4.5.4, OS X 10.5.6

I've run the calibrate by eye business but have not yet done a hardware calibration of this monitor.  Hoewver, even if I turn off color management in Photo Mechanic, I'm still getting the same effect. 

Also, just to try it, I grabbed the Google logo from the main Google page (hey it has bright colors) and noticed the same thing with it.  I've attached a screen shot of what I'm seeing.  Mind you if I put the preview at 100% it matches the contact sheet.



[attachment deleted by admin]

Offline tgray

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Re: Color difference in preview at 100%
« Reply #6 on: January 23, 2009, 05:49:16 PM »
Hmm.  Once I got home and I used my laptop disconnected from the external monitor, this problem went away.  I'm not sure why it was affecting Photo Mechanic but it seems to be a system wide thing while using that monitor and the display profiles for it, both the 'calibrated' one and the factory one.  So I'm not so sure if its worth looking into any more.

Offline Kirk Baker

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Re: Color difference in preview at 100%
« Reply #7 on: January 23, 2009, 05:55:32 PM »
Hmm.  Once I got home and I used my laptop disconnected from the external monitor, this problem went away.  I'm not sure why it was affecting Photo Mechanic but it seems to be a system wide thing while using that monitor and the display profiles for it, both the 'calibrated' one and the factory one.  So I'm not so sure if its worth looking into any more.

OK.  I was unable to duplicate your issue on my own systems, and I tried repeatedly.

-Kirk