Elevation gain?

In article ,
Derick Fay wrote:
On Feb 25, 7:10*pm, Camilo wrote:

Not to burst your bubble but I've got elevation gains of 1000s of feet
while using the 305 on a bike on a trainer and 100s of feet while
doing 800m intervals on a track. I like the device (had it for 9 mos
or so) but I've found it to be really inaccurate for elevation. You
can use the elevation correction function at motionbased.com for a
more accurate reading, or maybe if you're somewhere with very clear
skies you'll get better results.

Have you updated the original firmware on the device? Newer
versions work much better. Unless the folks at
www.motionbased.com have significantly changed their algorithms,
I have found their elevation totals to be useless except for
feeding your ego. I gave up on them about a year ago after
several email exchanges with the developers. They pretty much
didn't want to admit that the problems even existed.

They do have some nice toys to play with though. Just don't put
too much faith in their numbers.

_ Booker C. Bense

In article ,
Camilo wrote:
On Feb 26, 12:13 pm, "
wrote:
why not just estimating the elevation gain using a USGS topo map?

I've done that for many wilderness routes. However I don't have a map
of this particular area and would rather use my new toy anyway!

I'm hoping I will find it reasonably accurate for cycling this
summer. Just for grins, I'm going to set myself some elevation goals
for the season.

I've found it to be pretty accurate wrt to several very well
known and measured climbs in the SF bay area. It also agrees
quite well with the climbing totals for some hilly centuries
in the area. It's not perfect, in particular steep narrow
canyons, will often yeild very overstated results. If the numbers
could be believed for some Marin Country rides, I would be
competitive in the TDF.

Upgrade the firmware..

_ Booker C. Bense

Booker Bense wrote:
In article ,
Terje Mathisen wrote:
Camilo wrote:
Just got a new toy: Garmin Forerunner 305. I went on one of my
favorite skis and came up with the following data.

Distance: 25.5.km
Total ascent: 885 m (2,900 ft?)
If the ascent is spread over just a few large climbs, then GPS data will
be pretty good.

For rolling terrain, with lots of small (2-10 m) ups and downs otoh, you
really need a gps with barometer assistance to get good measurements.

The Forerunner has a barometer,

No, the 305 (and for that matter, my 301) doesn't have a barometer.

in general it's pretty accurate
wrt to altitude even in rolling terrain. Trees and very steep
canyons give it a bit of trouble, but for training purposes it
works better than any previous GPS I've tried.

I'm happy with my 301 - I'm told the 305 is even better.
-Bob