Originally Posted by
Seattle Forrest
But the OP - the person who's in the market for a new computer and asking for advice - thinks altitude is important. And that's the person who's going to use the thing.
Right. I'm not saying it's unimportant to all. It's unimportant to me, and seeing that, [MENTION=385397]pwcfan[/MENTION] (the OP) might find it useful, and as a result, he might be happy with an altimeterless computer.
Originally Posted by
dr_lha
I have no insight as to how the altimeter in a iPhone calibrates. However, I have plenty of experience in comparing "elevation change" numbers on group rides. My experience is that everyone's computer gives a different number, with those variances over a 30 mile ride being usually around 500ft different min to max. The Sunday ride was worse than this mainly because it was raining.
Regardless I see no evidence that the Garmins do a better job than my iPhone's app at estimating elevation changes. None at all. All my evidence tells me is that barometric altimeters mostly suck at calculating consistent elevations changes between units.
iphones have no altimeters. I believe smartphone apps and Garmins use knowledge of elevation built into the map data. This knowledge is not very accurate yet. I might be wrong, and perhaps some Garmins have altimeters, but not all of them.