Does a white background eat more battery?

Anton said:

so yes, I see a big difference of a factor of 3 between white and black background.

with a non-Garmin watch face. Try the same experiment with a stock watch face.

I was wondering if anyone uses those? 

Just checked, on Garmin orig it says 0.0-0.1 per hour on black. And it was 0.3 per hour on write. Looks like we found an issue)

Out of curiosity, does vibration alerr eat more battery or sound alert? I never tested it, just thought I dont need both, since F5+ is not so good at making a long battery life.

A piezo beeper is very energy efficient, so I guess it will. 

Guessing is no good though. Every time I see a question like this, I'm tempted to do set up an experiment. It is a compulsion I am learning to control. Feel free to do what I want to do, but don't have the time for:

Hard reset watch to defaults, use stock watchface. Charge watch to exactly X %. Note the ambient temperature. Set timer to repeatedly give an alarm (vibrate only, backlight off) every minute for an hour or two. Note battery level.

Repeat including reset. Make sure temperature is the same. Use beep alert this time. 

Ideally, get ~ 15 friends to do the same. 

Compare and post results.

Ideally you have a longer test period than a couple of hours, moreover you start your test always from the same fully charged state, because the battery level indicator is not accurate enough (the decrease of “percentage” is far from linear even in case of passive “usage”)

Anyway thanks for your opinion.

There are too many factors present to draw a conclusion based on one trial in my opinion. Sometimes my watch to seems to burn through battery faster without any apparent reason. For example, it always seems like the battery loses charge slower in the first 50%, but faster in the latter 50%. 

But not all garmin watches use the same display technology. Some have chroma-display, some have amoled: www.youtube.com/watch