Hi Dan, Tom, Ricardo, and Others, OK, here's the results about iMac screen brightness for all the inquiring minds that want to know. Apparently, the level of screen brightness is, indeed, characteristic of the iMac backlight, and not a property of Macbooks. I did some Google searching, and the first item I turned up was a program to dim Mac monitors. There are apparently a bunch of these, but here's the first one I found, which is a free program named "Brightness Control" with the subtitle "Dim your monitor easily": http://www.macupdate.com/app/mac/10429/brightness-control
That's the macupdate page for the program, and what's interesting is that there are other, similar programs to dim iMac monitors. However, one of the comments claims that although the program dims the pixels on the screen, it doesn't turn off the backlight, so the amount of energy being used is the same -- as though you had the screen curtain on. Also, apparently the color balance gets thrown off when the program is run. This still might be useful to Tom. The other interesting page was from a page by "Midwestern Mac, LLC", and it's a blog post titled "How to Save 20 Watts while Running an iMac (or another Mac)": http://www.midwesternmac.com/tutorial/2009-05-21/how-save-20-watts-while-running-imac You can read it with Safari reader (Command-Shift-R on the page to read the article text without distracting links). The quick summary is that the blogger tested his 2008 iMac connected to a UPS that also monitored the power usage of connected devices. Even with the display set to lowest brightness, the computer used about the same amount of power as a 77 watt light bulb. Turning the screen of the iMac off dropped that to 30 watts, and putting the computer to sleep took that down to 4 watts. But because the backlight on the monitor was always on, as long as the screen was turned on, it continued to use a good deal of power. My guess is that they can't afford to sustain that kind of power consumption on laptops because they're often run on battery power. Anyway, here's an excerpted quote from the blog article giving the stats. You can read more details about the experiment using the link that I gave above: <begin quote> Detailed stats, for those so inclined: • Computer on, running a bunch of processes, full brightness = 125 Watts • Computer on, highest brightness = 100 Watts • Computer on, lowest brightness = 77 Watts • Screen turned off (press Shift + Control + Eject) = 30 Watts • Computer sleeping = 4 Watts average • Computer off = 0 Watts <end quote> Very interesting, since it explains that all these iMac monitors don't really get down to 0 light level when you decrease brightness. It also means that even if you dim the screen pixels even further, by using a program like the one I mentioned at the start of this post, you're still using power that will show up in your electricity bill. HTH. Cheers, Esther On Jun 10, 2011, at 17:24, Dan wrote: > Another comment regarding screen curtain on my 27 inch iMac late 2010. Both > my wife and son said that when the screen curtain is on, the screen is still > lit and there is a cursor on the screen. Again, this is a brightness setting > of 0. > HTH. > Dan > > On Jun 10, 2011, at 8:02 PM, Esther wrote: > >> Hi Dan and Others, >> >> I've never checked display brightness with an iMac screen. On all the Mac >> laptop screens I've used, setting screen brightness to 0 seems to have the >> same effect as turning on the screen curtain. That's why I asked whether >> this was an iMac and what the display settings were in terms of automatic >> adjustment under System Preferences. I'd be really surprised if a laptop >> user said the screen stayed bright a 0 level display brightness setting. >> >> Cheers, >> >> Esther >> >> On Jun 10, 2011, at 16:52, Dan wrote: >> >>> Hello, >>> When the screen brightness is set to 0, my family can still use the iMac's >>> screen without any problems what so ever. >>> >>> Dan >>> >>> On Jun 10, 2011, at 7:38 PM, Esther wrote: >>> >>>> Hi John and Tom, >>>> >>>> Are you sure that you're using the appropriate keyboard shortcut? On my >>>> Macbook Pro, where I have checked the box for "Use all F1, F2, etc. keys >>>> as standard function keys" on the "Keyboard" tab of the "Keyboard" menu >>>> under "System Preferences", using the Fn+F1 key to lower the display to >>>> where it says keyboard brightness is "0 per cent" has the same effect as >>>> turning my screen curtain on, according to other users. This also checks >>>> out if I try to use the iPhone "Light Detector" app; I get no sound when >>>> the iPhone is pointed to my laptop screen when the display brightness >>>> reported by VoiceOver is "0 per cent" -- same as with my screen curtain >>>> turned on. As soon as I start to raise my screen brightness with Fn+F2 >>>> the "Light Detector" app on the iPhone picks it up. Of course, if I don't >>>> press the Fn key along with the F1 or F2 key, nothing happens to the >>>> brightness adjustment with the above settings. >>>> >>>> Are you using external displays like with an iMac? Also, what setting do >>>> you use when you check your "Displays" menu under System Preferences? >>>> Under the Display tab is the box for "Automatically adjust brightness as >>>> ambient light changes" checked or unchecked? When you interact with the >>>> slider and push it all the way down to 0 does your screen go dark? >>>> >>>> Cheers, >>>> >>>> Esther >>>> >>>> >>>> On Jun 10, 2011, at 15:40, John Sanfilippo wrote: >>>> >>>>> Wow! I quite aggree with your need to dim the screen even further than it >>>>> currently allows. I've resorted to the screen curtain (shift vo f11), >>>>> though that's not really the answer. >>>>> >>>>> Thanks for sharing. >>>>> >>>>> John S >>>>> >>>>> >>>>> On Jun 9, 2011, at 10:25 PM, Tom Frank wrote: >>>>> >>>>> Hi all, >>>>> Even at zero percent the screen is too bright for me to see maps on >>>>> Google . Is there any way to dial down the brightness even further? It >>>>> may be limited because screens are now LEDs and not CRTs. >>>>> Tom Frank >>>>> vermont...@gmail.com >>>>> >>>>> >>>>> >>>>> On Jun 8, 2011, at 10:21 PM, Ricardo Walker wrote: >>>>> >>>>>> Hi, >>>>>> >>>>>> Why not just leave it at 0%, and then when a person needs to see the >>>>>> screen, just press function F2 to brighten to the persons desired level. >>>>>> Then, just press Function F1 to lower brightness back to 0%? >>>>>> >>>>>> Ricardo Walker >>>>>> rwalker...@gmail.com >>>>>> Twitter, Skype, and AIM: rwalker296 >>>>>> www.mobileaccess.org >>>>>> >>>>>> >>>>>> >>>>>> On Jun 8, 2011, at 9:22 PM, Shameless FanGirl wrote: >>>>>> >>>>>>> Hi again all, >>>>>>> >>>>>>> For those of you who choose to dial your brightness down on your Mac, >>>>>>> but who choose to have it bright enough to be able to be adequately >>>>>>> viewed, should you need it via sighted assistance, I'm told it's still >>>>>>> perfectly fine at 10 to 15% brightness. Just thought I'd share that >>>>>>> observation with the list. >>>>>>> >>>> -- You received this message because you are subscribed to the Google Groups "MacVisionaries" group. To post to this group, send email to macvisionaries@googlegroups.com. To unsubscribe from this group, send email to macvisionaries+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/macvisionaries?hl=en.
