When the Mac first came out, one of its great WYSIWYG features was that a pixel on the screen was supposed to be equal in size to a printerâ€™s point: 1/72â€³.
On a 11â€³ MacBook Air, a 72-pixel lineâ€”which would measure 1 inch long against an onscreen rulerâ€”is just 0.53 physical inches long. On a 21.5â€³ iMac, that same line is 0.70 inches long. User interface items, like buttons, menu items, and scroll bars are 30% bigger on the iMac than on the Air.
Aside from the newly introduced MacBook Airs and the 17-inch MacBook Pro, most Macs have a resolution that is within a tight range of 109 to 113 PPI.
The resolution on new Macs seem to be converging around 130 PPI. The 11.6-inch MacBook Air has a range-topping 135 PPI while the larger 13.3-inch version has 128 PPI. The 17-inch MacBook Pro has 133 PPI. If you consider the 1680×1050 option on the 15-inch MacBook Pro the resolution increases from 110 to almost 129 PPI.
Next generation MacBook and Pros will most likely change:
- 13.3: 1280×800 to 1440×900
- 15.4: 1440×900 to 1680×1050 standard
That leaves the iMacs. If the 21.5-inch iMac goes from 1920×1080 to 2560×1440 the resolution increases from 102 to 137 PPI. The 27-inch iMac will need to increase to 2880×1800 (double 1440×900) to get to 126 PPI.
Although not exactly the same a tight range around 130 PPI for all Macs will make the overall experience similar.
The original Macintosh had a 9-inch monochrome CRT display and had a pixel format of 512×342. That’s about 68 PPI. Interestingly that’s also about half of what the new Macbooks are converging toward. So maybe the new Macs’ great WYSIWYG feature will be that 2×2 pixels on the screen will be equal to size to a printer’s point: 1/72″.