Display Quality: Color Gamut
Gaming on a PC is arguably more fun when you have a good display to match, but that also holds true for anything you do on a tablet. I don’t like to rely on subjective opinions in order to evaluate the quality of a screen, but there is almost no way to benchmark the IPS panel on Apple's iPad 2. On the desktop, we have programs like CalMan and ColorEyes to test a monitor’s performance, but these programs don’t work on mobile operating systems. Even if they did work, iOS doesn’t honor ICC profiles.
No program currently exists to test the performance of a tablet's LCD panel, which is why I spent the few weeks last month creating a custom program. The whole process is a little complex, but briefly, I’m measuring the color gamut at the display’s native settings (native gamma and white point) with a Spectracal NIST-certified i1Pro.
Even though mobile operating systems don't honor ICC color profiles, native color management does occur at the hardware level. When a GPU sends 10 different hues of blue to an LCD only capable of displaying three, the subpixels display the closest matching color. So in a way, smartphones and tablets behave like they’re using relative colorimetric rendering (for more information read our printer paper benchmarks).
Apple hasn’t really changed the technical performance of its iPad 2's IPS panel. The contrast ratio is better thanks to deeper blacks, but honestly, I’m actually a bit surprised at the low gamut volume. It’s about what you get out of a cheap TN-based LCD. Most people won’t complain because Apple sets the saturation too low, while increasing gamma and contrast. This makes color accuracy a bit harder to discern. However, if you’re a photographer who’s fussy about color, you’ll want to reconsider using the iPad 2 as a field tool. Compared to a notebook, you’re losing a lot of detail in blue shadows and midtones. This, in turn, causes some detail loss towards the magenta border in highlights as well.
Understand that these gamut measurements carry a few assumptions. First, we're disabling dynamic brightness because it doesn’t allow us to get an accurate (or reproducible) measurement of the display’s potential. Second, brightness is set to the highest value. If you don't use the same settings, your color gamut is going to look smaller than what we're showing here.
Apple continues to using a 1024x768 LCD display with 132 PPI (pixels per inch). So, the size of the individual RGB subpixels hasn't changed when we examine them under a microscope. Though, for some odd reason, the shape of an individual subpixel looks different. I suspect that Apple is using another manufacturer for the LCD panels in the iPad 2.
