Saturday, October 20, 2007

I’m pretty happy with my current-model MacBook Pro 15”. I got the Santa Rosa based 2.2 GHz model via a very good education price deal (I work in a university), and it’s a great all round machine. Because I take lots of photographs, I have calibrated the MacBook Pro’s display as well as my 23” Cinema Display so that I get true colors when preparing photos for web or print. I used the Spyder2 Express from datacolor, which is a great little gadget. The idea is very simple: you use the supplied colorimeter to look at your monitor while an application displays swatches of known colors. The colorimeter reports the actual color appearing on the monitor, and the controlling application creates a table that records the difference between the RGB values in the swatches and the ones recorded by the colorimeter. This is known as a device color profile and the Mac can use its generic factory-shipped ones, or the more accurate ones you create for your own displays with the Spyder2 or similar devices, to calibrate your screens. Once you’ve done this calibration, you can be confident that the colors displayed on your monitor are as close as is technically possible to the colors the original creator of the image or graphic design intended.

So I ran the calibration process and used the new profile. It looked richer and crisper, and prints I made using Adorama and Apple’s printing service accessed via Aperture were true to the colors on my screen. Photographically, everything was perfect. However when using NetNewsWire, or looking at certain sites such as Facebook, I noticed that a range of greys would actually be displayed as pink (see first image). I re-ran the calibration process a few times but still got the same result. I wasn’t happy with this - it was annoying me, and I spend enough time looking at this screen for it to matter.

I searched a load of Mac sites using Google’s Mac-specific search, and didn’t find anything helpful. I then turned to Apple’s Discussions Forum for the MacBook Pro and found a couple of articles which narrowed the problem domain to people exactly in my situation: they’d got a new MacBook Pro with the LED backlight and calibrated it with a Spyder2 or similar device. It seemed that the problem was that the current Spyder2 software, version 2.3, was hard-coded to use a white point of D65 (equivalent to the color of light emitted by something heated to 6300° Kelvin, and for years regarded as the best technical definition of the actual color of daylight). From information in the discussions it was clear that version 2.2 of the software still had the white point hard-coded to whatever the display’s hardware regarded as white (Native white point) and this was preferable in this particular case to what Version 2.3 used to create the profile. Luckily Datacolor makes version 2.2 available on its web site, so I went there and fetched the older version. I chose to put the old version of the software in a folder called Applications in my home directory, instead of the main Applications directory.[1]

I ran the old version of the app, and let it do its thing. When I looked at the display as managed by the new profile, it looked fine - the pinks had gone (see figure 2). Then I turned the Cinema Display back on, which had been off because, as my friend David says of a similar screen, you could light a cigarette using its output and a cheap lens at 50 feet. In fact it’s so bright that as the sole light source in our living room it will let you expose a decent shot of the room at f/22, ISO 400, in only two seconds. Spillage from this monster would have biased the calibration process. Cross checking with the Cinema - which was my reference screen - showed that while the greys were now pleasingly neutral, the whites on the MacBook Pro were now a faint but nauseous green. I tried to stick with this state of affairs for a day or so, but as I switched my attention between the Cinema and the MacBook Pro displays, it was even more jarring than the pinkish greys, and I changed the profile back to the original one.

I was stymied. The old version rendered the greys correctly, but produced unacceptable whites. The new version had crisp clean whites but pinkish greys. The Apple standard profile was too pale and too blue. Running manual calibration on the Apple profile but setting the gamma to 2.2 instead of the historic default of 1.8 helped with the paleness but didn’t help with the pinks. The male line of my family is genetically blessed in taking lush, healthy heads of hair to the grave, but I was at risk of being the first of our line to die bald as a result of my frustration. The only solution seemed to be to get hold of either upgraded software for the Spyder2 or get a better system such as the Eye One Display 2.

The answer came, as it often does, serendipitously. I was reading and came across Dan Frakes’s review of various brightness controller apps for recent Mac models. I had not really felt the need for extra control of brightness of the displays I use - I thought I was managing quite well with the native keyboard-based controls for the MacBook Pro and the Cinema Display’s Star Trek-like touch controls on its right-hand side. Nevertheless something impelled me to try Shades. I installed it, and then pulled its onscreen brightness slider down a little to dim the display slightly. The effect on colors was dramatic - the pinkish greys became the most neutral of shades possible. I nudged the brightness back up and the pink flush returned. I used the hardware control to dim the display and instead of the neutral greys I expected, I saw darker pinkish greys. Clearly Shades is doing something different to what the hardware backlight control is doing. I don’t yet have an explanation but I’m heartily glad that I have a solution.

The lesson here is: never stop reading, never stop experimenting. You can even make an analogy with biodiversity: we never know what we might need until we need it, and at present we’re eliminating our options as to sources of rare and interesting molecules every time we let a Western feedstuffs company wipe out a tract of forest or jungle. We’ll pay for that, and maybe sooner than we think. In the Mac world, it’s the small developers like Charcoal Design who are accidentally solving problems they probably don’t even know exist. It’s in every Mac user’s interest to cherish and support them.

  1. One great thing about Macs is that applications are just files (they’re actually folders (directories) pretending to be files, but usually that doesn’t matter) and you can put them anywhere and call them anything you like. This is another great feature of Mac OS X - you can put any app in this folder and it works just as if it were living in the main Applications folder, but it can’t affect any other user on your computer. It’s very useful for trying out new versions of programs (or in my case, older ones).