Archive for February, 2007

Why can’t you turn off the iMac screen?

Friday, February 2nd, 2007

Why is there no way to turn off the screen on an iMac? I mean, properly turn it off?

It’s not something I thought about when I was thinking about buying an iMac – I just assumed it would have such a basic feature. For something that’s generally well designed and usable, this omission sticks out like a sore thumb.

I’m sure lots of people have their own reasons for turning off their computer screens. Here’s mine.

I run 3 types of nightly backups on my Mac (I’m paranoid). One does a rotating backup to DVD. One does an rsync backup to my wife’s iMac. And one does an rsync backup of our server in the UK (in case it ever goes tits-up).

And in a few months’ time, my iMac will be in the bedroom (I’m being turfed out of the office so we can turn it into a nursery for our upcoming wee nipper). So you can see why having the screen off might be a good idea. IN THE BEDROOM.

Here are the solutions I’ve heard from various people:

  • Just put the iMac to sleep. Er, then how are the backups supposed to work?
  • Turn the brightness all the way down. You’d think that’d work, wouldn’t you? But oh no – unlike Mac laptops, where zero brightness really does turn off the backlight, an iMac’s idea of “zero brightness” is “ever-so-slightly darker than maximum brightness”. Useless.
  • Set the display to sleep in 1 minute. There are even scripts available to do this for you (and reset the sleep time back to normal afterwards).

Setting the display to sleep is not a bad approach, apart from two fundamental problems. Firstly, I don’t want the screen to turn off in 1 minute – I want it to turn off now.

Secondly – and more seriously – it’s not reliable. What I mean is, the screen spontaneously and randomly turns itself on. This seems to happen when certain specific activities occur during the backup process – spinning up the DVD seems to do it, as does network activity. (I’m still trying to pin down exactly what triggers set it off.)

As you might imagine, having a gorgeously brilliant white screen is wonderful when you’re working on it during the day. It’s not so nice when it turns itself on at 3AM in your bedroom.

So that’s the current situation. Apart from cracking open the iMac and installing a manual switch for the backlight, the best I can hope for it probably to put a towel over the thing at night. Ridiculous for such an otherwise well-designed machine. If you’re thinking about buying an iMac, and you want it doing stuff with the screen off overnight, I suggest you heed this warning. Memo to Apple: Fix this. Now.

If anyone has a decent solution, please tell me. I would absolutely love to hear it.

UPDATE May 2:
Found a way to sleep the display instantly. :)