Home Shop Classified News, Stories Events Education Ridecamp Videos Cartoons AERC
Endurance.Net Home Ridecamp Archives
[Archives Index]   [Date Index]   [Thread Index]   [Author Index]   [Subject Index]

Re: [RC] GPS Accuracy - AprJhn

Hi, Angie,

Yeah, I'm saying that if properly set up, the GPS will measure the distance traveled into the ravine and out of it. If the GPS is taking a waypoint measurement every 5 minutes instead of every 5 seconds, you're going to get very different mileage. And the 5 second one is more accurate because it will follow you down into the ravine. Further, you have to guard against lost satellites. The antenna must be as high as possible and have the largest view of the sky possible. The more satellites the GPS can see, the more accurate the readings. And to get even more accurate, you can download the track into the computer and let a better processor make the calculations of distance and speed.

As for Pigeon Mtn folks measuring the trail distance and putting up markers on the GPS say-so...well, I don't have my doubts so much on the accuracy of a properly used GPS, rather I have doubts on the knowledge and ability of the user of the GPS. Just handing somebody a GPS and saying go mark the trail without any education on how to properly do that will result in inaccurate readings as well. If they kept losing satellites (possible, I'm sure...I rode Longstreet's Charge 25 a few years ago), the accuracy degrades. I'm sure that the surveyor's wheel is even more accurate, even if the GPS never lost satellite reception. But I'm not going to use a surveyor's wheel when riding a training ride or an edurance ride.

I'm not advocating the use of a GPS to mark trail for an endurance ride. Although, if I knew the people marking the trail knew what they were doing, I probably wouldn't pitch a fit about it. I do think that used properly a GPS is a very good tool for training. And it's not necessary equipment either. But I like it. :)

And for the record, I agree with you about the mileage. If I go to ride a 50 and it's a 65, I'd like the credit for the 65!

Nashville, TN

Rides 2 Far wrote:

the linear distance will be

pretty close to your actual distance. Within hundreths of a mile. > Not
tenths, not miles. Hundredths of a mile.

So, you're saying that going up and down huge powerlines, the GPS would
measure the distance down into the ravine, then straight up the other
side, not the distance directly across? I've got my doubts on that. When
I go to a mountainout ride and know my horse is winding around up and
down hills at between 7 and 10 mph. and it takes me 3 hrs. to go "18"
miles something is wrong.

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Ridecamp is a service of Endurance Net, http://www.endurance.net. Information, Policy, Disclaimer: http://www.endurance.net/Ridecamp Subscribe/Unsubscribe http://www.endurance.net/ridecamp/logon.asp

Ride Long and Ride Safe!!


[RC] GPS Accuracy, Rides 2 Far