New user

[orange crush]

Well, i have finally replaced my favorite watch with an altimax. I am brand new to barometers and altimeters and have a few questions finding the manual kind of vague.
1) The altimeter uses air pressure to determine altitude... Is that pressure at sea level, or the pressure that it shows in the barometer main window.
2) Does the altimeter need to be reset constantly or does it go back to the correct altitude (IE it changes through 30 or so feet while i am laying in bed, do I need to reset it in the morning???
3)What is the first thing that i should set, sealevel, or altitude, and does setting one affect the other?
I like the watch so far, but am weary that it may be too much work, or that I could be out in the woods and not know quite how to use my watch. Right now I can't trust it because I went down about 50 feet at work in a one story building, and thirty feet in my bed. I read in anohter thread that that is normal due to changes in air pressure, but does that happen out on the mountains or laying in the tent where access to references is practically nonexistant? Is there a good book with more detail than the (rather puny) manual that comes with this watch.
Thanks for any help or reassurance.
PS, could it be the battery causing the watch to constantly (seemingly) lose the correct reading?

[Steve]

1) Yes, the altitude would be be affected by the barometric pressure.

2) The altimeter should be set at times you wish to track altitude. Due to changes in barometric pressure your altitude will become offset.

3)Yes they do affect one another, if possible set the altitude.

You will want to check your watch with altitude postings. It is used more as a guide to help you locate your position with your maps.

[orange crush]

Thanks for replying. I am getting used to my watch slowly. i now realize that the pressure in the room messes with my altitude reading. I also see how it is neccesary to reset altitude when it is needed.
Two questions more though... according to the manual, weather reports give barometeric pressure readings. Are these always relative to sealevel, or absolute, or is there some way to tell? Do I need to set sea level pressure, altitude or both when i am resetting?
Thanks again!!
Alan