Make your display's gamma in Leopard match Snow Leopard

Jason (the author) was correct about the SnowLeopard switch to a default gamma of 2.2. Unfortunately it's not really true that you can "simulate" this by calibrating your display in Leopard. Why?

Because the changing your display profile's gamma will only visually affect the presentation of images that are not profiled aka color managed. For instance, go change your gamma as many times as you want and the photos in iPhoto, Aperture, or even Preview will look the same (you may have to quit the app and re-open for it to recognize the new display profile). This is true because all those photos are profiled! In a completely managed workflow, changing your display gamma shouldn't affect the presentation at all, you literally won't see a difference.

Here's the problem: In Leopard, most of the applications, and assets that make up the UI in the OS don't have color profiles. And likely none of the programmatic drawing code also isn't using a color profile either.

Those of you with the SnowLeopard seed can check this out, change your display profiles between 1.8 and 2.2 gamma. You'll see a flicker and then it should look exactly the same as it did before. The only exceptions are apps or parts of the system that haven't updated yet to be completely color managed.

So now you're asking, why bother changing the default display profile gamma if everything is going to look exactly the same? The answer: the Web.... and Windows. Windows doesn't typically have a color managed workflow, and applications on Windows rarely if ever attach profiles to assets created on Windows. And even when they do, they often get stripped out for posting to the web to make files as lean and small as possible. Despite the lack of a profile, everything users saw on the Windows machine while they were working was being displayed in a target gamma of 2.2. So when Mac users look at these photos, images, assets, websites that were created on windows, they look different! SnowLeopard fixes this by making the Mac default the same as the Windows and the Web (and TV, and everyone else.)

So in summary, if you just tried out 2.2 in Leopard and you hated the way it looked -- don't worry. SnowLeopard should look exactly the same (although your applications will most likely need to issue updates.)

Make sense?

Gamma correction should only be done on a display by display basis, not ad hoc system-wide (or platform-wide). If you have a CRT, it *may* be appropriate to apply a 2.2 gamma correction. If you have an LCD, it *may not* be.

For those still unsure what "gamma" actually is, historically gamma represents a non-linear variable in the modelling of the phosphor light response to the electron gun voltage in a CRT. However, it's been colloquially applied as a way of describing what needs to be corrected in the output of a display in order to make it look perceptually accurate (according to some CIE document recommendations, I think).

Charles Poynton has some excellent material which is worthwhile wading through if you have the time.

http://www.poynton.com/notes/colour_and_gamma/GammaFAQ.html
http://www.poynton.com/notes/mac/Macintosh_gamma_abs.html

I have a second question now. Playing in iPhoto, I'm seeing that since I changed the gamma to 2.2, any photo I view does a "flash" and seems bright. Like its setting the picture to 1.8. I checked my preferences and I have "embed ColorSync Profile" enabled. Should that be checked? and will this flicker still be present in Snow Leopard. What about new photos I add to iPhoto now? I assume they will be set to 2.2, and it should look fine, but I can't see anywhere to tweak with the existing photos to change the ColorSync profile.

Sorry, this is all rather confusing to me I guess.

I'm also one of those "no idea what this means/does" people. I went ahead and tried it on my 24" iMac, and its ok I guess. The loss of detail in the dark areas is super obvious on my MacBook Air with the default leopard background.

But I have a question for you graphics peeps: I went ahead and set the imac to this now (might as well get used to it). However, my external monitor (NEC MultiSync 20WMGX) seems to not like it much. The Apple Calibration Wizard made me move the contrast all the way up, then adjust the brightness, then readjust the contrast to find the gamma. Whatever it did, it doesn't really match the iMac at all. Like the whites are quite yellow on the NEC compared to my iMac. I can probably get used to the darker look and loss of shadow detail, but the now obvious mismatch of "white balance" between the two screens is really distracting. How the heck do I go about fixing this? I have no idea what 95% of the calibration wizard is talking about to be honest.

...

Tried to take a look at this..

Only to find that my Cinema 23" is set to 2.2...
Haven't touched anything.

Seems like the screen is adjusted to Snow Leopard....

"Multi-Touch gestures in
older Mac models.
All Mac notebooks with Multi-Touch trackpads now support three- and four-finger gestures."

Ha, so I was right! I had always thought that this would be possible with the old Macbooks trackpads, the multitouch scroll has been around for years... So why wouldn't it be able to handle twisting pictures?

Be careful if you use Final Cut Pro. The canvas expects a 1.8 display gamma, then displays the video with 2.2. If you change to 2.2 without OS support (I hope 10.6, or a future FCP update considers this) then you're going to end up with seriously bad color.

I don't really like 2.2 =(

Everyone toning photos on a Mac, amateur or professional, should be using 2.2 Gamma if you are not using a hardware colorimeter and accompanying software for calibrating your display. Using 1.8 Gamma so "you can see the shadow detail better" sounds great in theory, but the reality is you need to tone for the output/viewing medium, whether that is a print or other computers.

If you are using 1.8 gamma, the images will not look the way you intended when someone looks at them on a Windows machine, a Mac set for 2.2, on a TV, or printed. As an extension of this thought, it's better for something to look incorrectly brighter if viewed at 1.8. This is the lesser of two evils compared to toning at 1.8 and making things too dark when viewed at 2.2.

Nice... I quoted the wrong sentence. But luckily there's the "edit" option... Oh... wait... never mind...

It's been a hard day of work. Sorry for the misquote. I was referring to the "put back" option of the trash...