The huge blind spot in the testing of battery life for laptops

If you have purchased a laptop recently, I have no doubt that the runtime of the battery was an important criterion in your appraisal. Of course, that's probably the reason why laptop manufacturers--as with their mobile phone counterparts--publish battery lifetimes only ever achieved in labs under impracticable settings.

Thankfully, we have hordes of products and gadget reviewers who will gladly test out mobile devices or gadgets, publishing the results of their independent tests so that consumers can make a more informed choice. I was reading one such mini-review by Macworld assistant editor Chris Holt, who put Apple's new MacBooks through their paces, specifically to measure their battery life.

The test was conducted by playing a DVD movie ripped onto the hard disk, which is done to largely eliminate the optical drive from the equation. The movie was set to full screen, and the screen brightness was set to the maximum possible for the test. Why set the display brightness to the maximum? The reason is to simulate the low lighting in an aircraft cabin, Chris helpfully explains. Now, this makes sense on one level, but it is also an issue that got me thinking.

You see, I only ever set my laptop display to maximum when I am working say, at an outdoor café at noontime. When on battery, I always set it to six out of eight bars (6/8), which is perfectly adequate. Honestly, setting it at anything more than 4/8 in a dim room is not tolerable to my eyes for anything more than a few minutes. Additionally, on my laptop at least, a setting of 4/8 increases my battery life by more than an hour over a setting of full brightness.

What I am saying here is that there is a huge blind spot in the testing of battery life where laptops are concerned. Unlike desktop LCD monitors, the relative brightness of laptop displays is an area rarely considered. This is despite the huge difference it often makes to the battery runtime of the laptop. Ironically, manufacturers with an eye for quality are more likely to put in a brighter LCD panel than one focused on cost savings. The inevitable result is that higher quality products get penalized in battery comparison tests.

What about you? Do you run your laptop at full brightness all the time? - Paul