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Mike Coscia

macrumors member
Original poster
Jun 25, 2007
53
0
I have it set to off right now at about 1/4 brightness. Is it better for it to use auto brightness to save battery power?
 

runplaysleeprun

macrumors 6502a
Jul 27, 2004
845
1
Chicago, IL
That's like a common sense question/answer...

I don't think so. I'd say it depends how often you are in low-light situations. If you are in low light situations often, it may save a small amount of battery to have it on auto, otherwise 1/4 brightness will probably save you more battery.
 

FreeState

macrumors 68000
Jun 24, 2004
1,738
115
San Diego, CA
http://www.apple.com/batteries/iphone.html

Optimize Your Settings
A few features use your iPhone battery more quickly. If you adjust these feature settings, your battery life will be improved.

Wi-Fi: Wi-Fi consumes power even if you are not using its features to connect to a network. You can turn it off to save power. Go to Settings > General > Network > Wi-Fi.

Bluetooth: Likewise, you can turn off Bluetooth to maximize battery life, as it also consumes power when not in use. Go to Settings > General > Bluetooth.

Auto-Brightness: Turning on Auto-Brightness allows the brightness to adjust based on current lighting conditions. Go to Settings > Brightness.

Equalizer: Adding EQs to playback uses more of your processor, since they aren’t encoded in the song. Turn EQ off if you don’t use it. If, however, you’ve added EQ to tracks in iTunes, you’ll need to set EQ to “flat” in order to have the effect of “off,” because iPhone keeps your iTunes settings intact. Go to Settings > iPod > EQ.
 

Avatar74

macrumors 68000
Feb 5, 2007
1,608
402
I have it set to off right now at about 1/4 brightness. Is it better for it to use auto brightness to save battery power?

Generally brightness doesn't change power consumption. What it does do is conserve the life of a light emitting element. The dimmer control in a circuit draws continuous power from a battery (or AC source) regardless of the amount of it passes through to the light at the other end of the circuit.

What WILL conserve battery power in relation to the display is ensuring that you put the phone in sleep/standby using the button on the top, to shut the display off entirely.
 

vinhmen

macrumors newbie
Jul 10, 2007
20
0
Generally brightness doesn't change power consumption. What it does do is conserve the life of a light emitting element.

If this is true, why does the power-save setting on my laptop automatically dim the screen when it runs off the battery instead of A/C power? I don't like the dimmer setting, but accept it because I thought it was conserving battery power. What is the point of any "power management" mode on a mobile device when it dims the display.
 

MacJediDude

macrumors member
Jul 12, 2007
47
0
If this is true, why does the power-save setting on my laptop automatically dim the screen when it runs off the battery instead of A/C power? I don't like the dimmer setting, but accept it because I thought it was conserving battery power. What is the point of any "power management" mode on a mobile device when it dims the display.

Just a guess here, but I know that old school screens do not use LED, but instead use florescent tubes.
 

mashinhead

macrumors 68030
Oct 7, 2003
2,957
835
i find the auto brightness doesn't really do anything, I just manually adjust mine because either it doesn't work is in intelligent enough to know when to work.
 

stealthman1

macrumors regular
Oct 20, 2006
240
0
Ca
Generally brightness doesn't change power consumption. What it does do is conserve the life of a light emitting element. The dimmer control in a circuit draws continuous power from a battery (or AC source) regardless of the amount of it passes through to the light at the other end of the circuit.

What WILL conserve battery power in relation to the display is ensuring that you put the phone in sleep/standby using the button on the top, to shut the display off entirely.

I'm not going to say you're wrong, but anecdotally, I just ripped out the plug on my MBP and at full brightness I had 4hrs 09min and at minimum 4hrs 38min?

My initial thought is auto-brightness off, as there must be a sensor being powered and if like you, I leave my brightness at 1/4 or less, there ain't a lot of adjustment being done to my eyes at least.
 

hapa8o8

macrumors newbie
Jan 14, 2011
1
0
Generally brightness doesn't change power consumption. What it does do is conserve the life of a light emitting element. The dimmer control in a circuit draws continuous power from a battery (or AC source) regardless of the amount of it passes through to the light at the other end of the circuit.

What WILL conserve battery power in relation to the display is ensuring that you put the phone in sleep/standby using the button on the top, to shut the display off entirely.

you could never be more wrong...
A/C is alternation current, used in structures such as building and other such faculties. As for DC, direct current, that is what is used in mobile devices, even cars and the sort.

A battery may charge from an AC source, such as a wall, but when supplying power to a device, such as a car or phone, it does so through a Direct current (DC).

Therefore, when you use more energy, i.e. blasting your twin 10" subwoofers with the air conditioning on full (analogous to your brightness being turned all the way up), as opposed to less energy, i.e. your car turned on (not running) but your radio is off (and you can still charge your phone, etc) (again, analogous with your brightness on the lowest setting) You'll notice a drain difference.

... Therefore, brightness does affect the battery life :):p
 

-aggie-

macrumors P6
Jun 19, 2009
16,793
51
Where bunnies are welcome.
Some of you are confused as to how auto brightness works for the iPhone. In low light, it actually gets dimmer and in bright light it brightens to the maximum you have it set at. This is done so you can see the screen in bright light settings, such as a sunny day. So, auto brightness is counter-intuitive.
 

saving107

macrumors 603
Oct 14, 2007
6,384
33
San Jose, Ca
you could never be more wrong...

you sure told that person, 3 and a half years later.

How do people find these really old threads and then have a come-back? The person you replied to posted that 2 weeks after the first iPhone was released, and considering the date, we all have more knowledge of how the iPhone works now.
 
Last edited:

Mauser59

macrumors newbie
May 9, 2012
1
0
Kudos to the person who replied 3 years later to answer the thread RIGHT! It doesn't matter if it's ten years later, that's misleading information that some stupid kid could have thought was true. There's nothing wrong with correcting the wrong answer. And AC and DC came out way before the iPhone did, the guy should have known what he was talking about, regardless of how short it was after the release of the iPhone. He was trying to act smart and got put in his place. There's no need for more wrong information on the web than there already is.
 
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