Discussion: GPS Mapping

What do you know about using GPS for Orienteering mapping?

While on that topic I noticed a photo of OCAD running on a pocket PC with GPS in a recent O-Sport. Is this technology available now?

I'm not aware of a Windows Mobile version of OCAD for pocket PC, but you can run WM versions of GIS mapping programs - ArcPAD - with GPS on Pocket PC. The data from those should be easily imported to OCAD. However most GPS units that work with Pocket PC's probably don't have the required GPS accuracy for O mapping. You'd still have to have an external differentially corrected GPS connected to the Pocket PC to get accuracy down to O standards.

Ed Hicks has been doing a lot with this lately, and Alan Young has been involved, although I don't know much about the details. I do know that it has involved a hat with a GPS receiver mounted on top, although maybe they've improved the setup. I think Ed mentioned using a tablet PC in the field in conjunction with this setup.

Personally, I've been pace-and-compassing an area near where I live in order to correct the trail map that was created by the town trail committee with GPS. (It will become an orienteering map eventually.)

Ed Hicks just posted a note about the upcoming OCAD 9 on the Clubnet. Among the many interesting new features is the ability to download waypoints and tracks directly into OCAD rather than going thru funky other software as now, and the ability to work live off a gps - if you have a wearable computer as Ed does.

Go to either the clubnet for the link or thru the OCAD.com site.

Sorry - Ed's posting is on the Omap net.

Having OCAD on a Pocket PC with a function that would center the map on current GPS coordinates would be useful. I've toyed around with writing my own program for taking field notes (which is much different from cartography) on a Pocket PC, but haven't got any further than a general design. IF I ever write it, it will have a GPS interface.

However, if you need a GPS to figure out where a feature actually goes you either

1) have a really crappy base map

and/or

2) aren't good enough at this to be mapping.

In either case, your final product will not likely be very good. I can usually tell pretty quickly if a map I'm on was made by someone who relied on GPS. It's not so much that it's wrong, just devoid of any interpretation.

It's kind of like what's produced by hitting the demo button on a Casio keyboard. Some people might wish they could play that well, but such an individual would be a bit of a fraud if they marketed themselves as a musician.

Of course, if a club can't afford a professional mapper, their options are limited. Even in such cases, I would strongly recommend JJ's approach of pacing rather than GPS. Pacing an area off gives you an appreciation for how it will be seen in competition that a single set of coordinates cannot.

The O-sport photo looks like a mock-up... The map image is too sharp for it to be a real photo of a pocket PC screen.

Also, I can imagine that mapping on a Pocket PC in direct sunlight might be hard due to screen brightness...

Not to say it can't be done, but I'm still using pen & paper (for my home-brew maps, that is...)

Actually, some Pocket PC screens are remarkably good in the sun. The HP iPac's are a particularly good example. The real problem is power. A pocket PC with an active screen turned all the way up will go through it's batteries in under 2 hours. Even less if it's driving a GPS as well. You need to get one of the big battery expansion packs to get anything useful done.

I have recently been using GPS in mapping. I find it is a great way to confirm the base map is accurate. I use the GPS to pick a spot and map by compass everything around it. I have been using this also for areas where I don't have base map. By the way, I used the GPS to confirm the the map I was updating was never mapped to magnetic north and we had been using the map for years

I wouldn't recommend my method of using GPS in place of a base map for a high quality map but it is a cheap way to get a local map. I use the GPS to take coordinates and plot that onto paper rather than directly into OCAD which I look forward to being able to do.

Carlsson and Svanberg have run PC-mapper on a handheld pocket PC attached to a GPS.

http://www.algonet.se/~cart/asmund.htm

I've not used any GPS to make maps, but I plotted the courses for a club championship on a scanned map, which was then imported into Ozi Explorer. Course length comes out automatically, and then I could download all points and courses (as routes) to my Garmin eTrex Vista. Thus I could check if the points were where I thought they would be. Rather good in a diffuse area, where there are 13 boulders, of which seven are on the map, to figure out which one you are aiming at.

I'm also running PathAWay on my iQue 3600. That program allows scanning and import of any map. Thus you can have an orientering map in your hand, and use the GPS as a reference to the map.
Not for competing, of course, but as an aid when organizing meets.

Besides, where I live, the recent hurricane has taken down a lot of the forests, so the maps will not be correct anyway.