I need help with Mac color management

sk66

sk66

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Name
Steven
Edit My Images
Yes
Recently upgraded to a late 2013 15" MBPR OSX 10.9.4 and I'm having an issue I can't sort.
When opening this Norman Koren test image in any browser the gamma shifts (it's *not* monitor angle or image position). Firefox with color management turned on ~ 1.8, Safari color managed ~ 1.4, and Chrome ~1.6. The luminance bands remain pretty constant.

But if I open the image in any other type of program (LR/PS/Preview/etc) it's consistent at ~2.15. I've recalibrated (color eyes display pro w/ spyder 3) trying a couple things. Noticed I had a V4 ICC so tried V2 (I can't seem to get V4 compatibility to work regardless). Set to defined 2.2 instead of LUT L*... nothing has made a difference. Checked the profiles are good and properly installed thru display settings and colorsync.

Not too sure how concerned I need to be either as colors don't shift around w/ the color managed browsers and the luminance bands stay pretty consistent. I know I don't need to be too concerned because my "desktop side" is all working correctly but it would be nice to know I'm seeing things "correctly" on the web (especially when giving advice).

The only thing I can think of is graphics card (NVIDIA GeForce GT 650M 1024 MB) -vs- integrated handling (intel HD4000) of some type. I had this all worked out on my 17" MBP...even V4 compatibility seemed to work. But it only had integrated graphics. I can't find anywhere to address use of graphics card vs integrated handling....

Any help will be greatly appreciated!
 
Disabled automatic switching in in power management, no effect. Found a program that allows me to manually select/switch between graphics (gfxCardStatus)... no effect.

I'm clueless...
 
Why are you trusting how this is rendered over your fairly robust calibration? It's just a PNG. Different browsers may, or my not be honouring the profile... if it has any (shrug). If it's any consolation, it seems to suggest my gamma is not 2.2 (it seems to indicate a little lower.... although let's be honest.. you have to squint and make judgements about where the margin lies) even though I have a high end ColorEdge monitor, hardware profiled with Eizo Color Navigator and a i1 Display Pro. I know which I'm going to trust :)

The image you're using is also not embedded with any colour profile....

h8Fctaz.jpg


...so how it's handled by various browsers will vary depending their colour management policy, regardless of whether they support ICC profiles... as the image HAS no ICC profile. Some will force sRGB, some will retain native RGB values etc... either way, as how it's rendered can effect contrast, this image will be rendered differently, and hence seem to indicate different gamma values in different browsers.

You have to remember, this image is intended as a ROUGH guide to those with no means of calibration. :) Trust me... don't worry about it.
 
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I realized it wasn't tagged when I pulled it into PS so I tried saving it out as sRGB jpeg with tag embedded... it didn't make any difference. I forgot to mention that. (FWIW, some browsers ignore embedded tags in png's anyway for some reason... another web/browser oddity. Edit: I think you insinuated that in your post...)

The thing that has me irked is that my system is supposed to be fully calibrated, to include the browsers I use (safari/firefox), and they apparently aren't. Yeah, I know it's "the web" and there's just no way to accommodate all of the variables... but I was hoping I could at least get my end consistent.

I guess, all-in-all it's very minor as the gamma shift is the only thing I'm seeing. Colors and luminance seem consistent. And everything seems to be consistent, including gamma, as long as I'm not using a browser... and that's what really matters. I just don't understand "why" I can't get it to display consistently in color managed browsers... I guess that's what bothers me more than anything else; not understanding.

FWIW, I just use the image as an occasional "quick check" just to make sure my calibration hasn't shifted too far. A while ago I found my ICC profile had changed to something else/wrong and I didn't know how it got changed or how long it had been wrong... That kind of sucked to sort out and correct a bunch of edits. Luckily it wasn't too far off and I didn't have many images that were important enough to require re-editing. Just opening the test image is a lot quicker/easier than calibrating/validating (but does nothing for colors).
 
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It's just a rough guide for those who can not, or do not calibrate. It's not a deadly accurate measure of gamma. Seriously... the best thing you can do is forget you've ever seen it. :) If something hoes seriously out of whack, you'll notice anyway.
 
Pookeyhead said:
If something goes seriously out of whack, you'll notice anyway.
Click to expand...
One would hope, but I didn't initially... Well, I guess that depends on your definition of "seriously out of whack."

I'll continue to use the image as a "quick consistency check." It's particularly useful for me in the luminance levels because my control/stability of environmental lighting for editing is seriously lacking... someday the remodel will be finished...
 
@sk66

Your ambient lighting won't effect the screen's gamma though. That's a property of the screen calibration, not a perceptual issue.
 
Yeah, I meant the right side of the image/black levels... just a check of ambient vs screen brightness. Or if the gamma point should shift significantly for some reason (not concerned about "where it's at," but rather if it changes).
 
sk66 said:
Yeah, I meant the right side of the image/black levels... just a check of ambient vs screen brightness. Or if the gamma point should shift significantly for some reason (not concerned about "where it's at," but rather if it changes).
Click to expand...


If it changes at different places around the screen, again, that's not a calibration issue, but a hard fault with the monitor. Calibration is a global adjustment across the whole panel, so any inconsistencies are with the panel, not the calibration. Technically you are calibrating your video card, not your monitor.
 
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Pookeyhead said:
If it changes at different places around the screen, again, that's not a calibration issue, but a hard fault with the monitor. Calibration is a global adjustment across the whole panel, so any inconsistencies are with the panel, not the calibration. Technically you are calibrating your video card, not your monitor.
Click to expand...
Surprisingly it's quite consistent on the (retina) screen even with varying angles/positions.... most LCD's require a bit more care in viewing angle/position.
By "where it's at" I didn't mean on the screen... I meant where it indicated the gamma level was set. It says ~2.15 for my setup so as long as it continues to say ~ 2.15 it's fine.
 
OK.. now I understand.
 
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