What the new Ali-imac's real Gamma?

[Andrew ren]

hey folks,

got a 20inch Aluminum imac couple weeks ago.

when i was doing the calibration, i noticed that the adobe 1998 file is kinda of blueish. very noticeable. even after I have been keeping rerere-calibrated under their expert mode for almost 10 days, 4-5 times per day. guess what, almost the same result, minor contrast difference, but all blueish.

So this morning, I haul my imac over to the work, here I have a big mac environment, 10 macpro towers, 20 cinema hd displays. I lined up 6 CinemaHD display and one older white imac 20 along with mine own Ali-imac 20. the blueish is VERY distinguishable!

tried to match the Cinemas, failed miserably.
then I turn off the "expert" mode on my imac, changed the gamma from 1.8 to 2.2 and keep the native point(6507k), then bum, it looks pretty close. blue was gone.

To my eye, the Cinema Hd has more dynamic range for sure, that is white is whiter, black is blacker. despite they all seems warm-tuned, but the white is pure white. on the other hand, the old imac is also looks warm, but the white isn't pure white to me.

All the cinema HDs are all in adobe 1998 mode, so as the other 2 imacs.

for the price of my imac, I am very happy now, I almost went over to buy an eizo ce22. :-0 probably it's time to invest on a good calibration set.

Andrew

[Joanna Carter]

It really is very simple; if you want good colour calibration, use a calibration tool and software, not the built-in utility. The fact that other monitors seem to be "better" is just as subjective as your opinion that your monitor is "worse". Truth is, an uncalibrated monitor can only be "better" or "worse", a calibrated monitor will be "correct".

[Ken Lee]

What Joanna said.

Given the substantial investment in hardware that you mention, it is very surprising that someone seems to have overlooked the importance of calibration.

Calibration has to be performed on a regular basis, since monitors "drift", each in their own way.

Given that much hardware, I would call someone at CHROMiX (http://www2.chromix.com/index.cxsa)and see what they can do for you.

[Andrew ren]

Joanna, well said!

what I am trying to give out the info here(as an new user to the new imac) is that set your gamma on 2.2 instead of 1.8 (which is sort of standard of mac system), will give you a much closer "look" to match a well-corrected Cinema hd display. Well, just sharing my 1st-hand experience.

Ken,

Thanks. just talked to rick @ chromix. will let him know after some research work i need to do. :-)

A

[Tyler Boley]

the long standing folk wisdom about about the platform's native gamma has been irrelevant for some time now on a color managed system. Assuming you have a calibrated monitor, and use color managed imaging applications, what your gamma is set to, and/or what platform you are on, is "corrected" for via the various profiles involved- monitor, working space, etc... and will appear the same regardless.
For serious work these assumptions have to be made, and if you are not calibrating your monitor and using color managed apps, that would be a very good first area of pursuit.
Where these setting do make a difference.. in non color managed situations- the finder, possibly some browsers, other low level imaging apps, etc.. but we have little control over those situations anyway. Assuming so much is done with browsers these days, 2.2 is probably a good standard for either platform, for the monitor gamma.

Hope that makes sense.
Tyler

[Andrew ren]

did a spider 3 pro cal this afternoon.

4 icc files:

gamma 1.8 @ full brightness
gamma 1.8 @ half brightness
gamma 2.2 @ full brightness
gamma 2.2 @ half brightness

I end up pick up the 2.2 @ half, as it balanced my web-surfing and PS the best.

If I won't recommend the ali- 20 imac to anyone for ps work, you need to sit right @ the centre of the screen to make it right, 15 degree off you will see one side turn yellowish. different panel from the 24".


Andrew

[Scott Kathe]

I end up pick up the 2.2 @ half, as it balanced my web-surfing and PS the best.

If I won't recommend the ali- 20 imac to anyone for ps work, you need to sit right @ the centre of the screen to make it right, 15 degree off you will see one side turn yellowish. different panel from the 24".


Andrew

Early last fall I picked up one of the older white units with the matt screen for home photography use because I didn't like the glossy screen when I checked them out in a local store. I have one of the new glossy screen iMacs at work I'm very impressed with the older iMac screen and not very impressed with the newer glossy screen. The gloss doesn't bother me so much-when I change my viewing angle by just a little bit the colors change a little bit. I wouldn't be happy doing ps work with the glossy screen.

Scott

[Andrew ren]

Scott,

we are opposite. I have an older white imac @ work. :-0

yes, I might start to think about getting a new panel for ps work. One of my friend recommended this IPS panel to me.
http://hardforum.com/showthread.php?t=1319356
same panel as the NEC, but much cheaper.

anyone?