Brand new Oregon 450T not accurate?

[+psubrian]

Hey gang - I just picked up an Oregon 450T over the weekend and I've been really excited about the chance to use it. I got the batteries installed, started doing some minor config to the menus and did the electronic compass calibration. Imagine my shock when I let the satellites acquire and the map showed me on the opposite side of my cul-de-sac, about 300 feet away. I shut the unit down, powered it back up, and the same result. Today I connected it to the website, did the update, powered on/off etc, and it's still showing me on the oppposite side of my cul-de-sac. Has anyone else experienced this before? I'm really bummed and not sure what else to do at this point.

 

psubrian

[+ecanderson]

Hey gang - I just picked up an Oregon 450T over the weekend and I've been really excited about the chance to use it. I got the batteries installed, started doing some minor config to the menus and did the electronic compass calibration. Imagine my shock when I let the satellites acquire and the map showed me on the opposite side of my cul-de-sac, about 300 feet away. I shut the unit down, powered it back up, and the same result. Today I connected it to the website, did the update, powered on/off etc, and it's still showing me on the oppposite side of my cul-de-sac. Has anyone else experienced this before? I'm really bummed and not sure what else to do at this point.

 

psubrian

Surprise - no map has ever had all of its roads geolocated with great precision. That's why manufacturers of automotive units employ a trick called "road snap" that shows your vehicle on the nearest possible road to the currently received coordinates. If not for that, your unit would display some interesting off-road adventures that didn't actually happen. Fire up Google maps with a satellite view and "labels" turned on. Interesting to see where some of the roads are 'mapped' vs. where they actually are.

 

So never be surprised if you're standing in one place and the map shows you in a slightly different position. It's the state of the technology at the moment.

 

Also - don't forget, your GPS has some error, too. Check to see what it says about its current 'accuracy' when you're out there next time and assume that error could also be a factor.

Edited May 17, 2011 by ecanderson

[+psubrian]

I knew I'd forget to mention the accuracy - its telling me 12 feet. Even my Nuvi knows what side of the cul-de-sac I live on.

 

Hey gang - I just picked up an Oregon 450T over the weekend and I've been really excited about the chance to use it. I got the batteries installed, started doing some minor config to the menus and did the electronic compass calibration. Imagine my shock when I let the satellites acquire and the map showed me on the opposite side of my cul-de-sac, about 300 feet away. I shut the unit down, powered it back up, and the same result. Today I connected it to the website, did the update, powered on/off etc, and it's still showing me on the oppposite side of my cul-de-sac. Has anyone else experienced this before? I'm really bummed and not sure what else to do at this point.

 

psubrian

Surprise - no map has ever been geolocated with great precision everywhere. That's why manufacturers of automotive units employ a trick called "road snap" that shows your vehicle on the nearest possible road to the currently received coordinates. If not for that, you could have some interesting off-road adventures.

 

So never be surprised if you're standing in one place and the map shows you in a slightly different position. It's the state of the technology at the moment.

 

Also - don't forget, your GPS has some error, too. Check to see what it says about its current 'accuracy' when you're out there next time and assume that error could also be a factor.

[+New Jersey TJ]

Following on EC's post, make sure that you are NOT set to lock on the road for this test. If that is turned on, you might be snapping to that location instead of where you really are.

 

What maps are you using?

Edited May 17, 2011 by New Jersey TJ

[+kunarion]

the map showed me on the opposite side of my cul-de-sac, about 300 feet away.

Do you have auto-routing maps installed? If so, in the menu, select "Off-Road" for Routing. If the Oregon is picking the nearest road, it can show you quite a distance away. You should be able to select the Geocaching profile, and be Off-Road, but be aware that any profile can be changed for better or worse.

 

One other very important thing for a brand new Oregon is it takes a long time to get its bearings at first. Off the top of my head, I think it's recommended to let it acquire for 15 minutes, but I'm not sure. After that it should be much faster.

 

Visit a couple of nearby Geocaches (sats as unobstructed as possible), and see if it's still 300 feet 0ff. I set up my caches using a 450T, and the first one is verified within 4 feet of the coords. Unless something's terribly wrong with yours, it should be accurate.

Edited May 17, 2011 by kunarion

[+JPatton]

Have you loaded any detailed maps? The base map is usually not very accurate and could easily be several hundred feet off.

[+psubrian]

All really good questions, and I appreciate the willingness to help me out. I just have the default map installed currently, the TOP U.S. 100K. I have no idea if its an auto-routing map. What I do know is that under ROUTING, I have Guidance Method set to Off Road, Lock On Road is No, Off Road Transitions is Auto.

 

I know there are probably a million posts on getting other maps, some of which I know can be free, so I just need to read through those threads and figure out what maps I even want or need and then do it. I hope that helps what I perceive to be a problem.

[yogazoo]

The pre-installed topo maps on the 450T are the 100k series that use Tiger 2000 data for roads which is notorious for being several hundred feet off in certain areas. As stated, your maps are the culprit and not your GPS. If I were you I would go out and grab some of the free maps that are available. Some may use the same road data but chances are there are better road representations out there for your area. If that doesn't work you could load some custom aerial imagery for your location and check the accuracy with that. No map, whether raster or vector, is perfectly accurate but you'll probably get closer to the truth with some than others.

Edited May 17, 2011 by yogazoo

[+ecanderson]

I know there are probably a million posts on getting other maps, some of which I know can be free, so I just need to read through those threads and figure out what maps I even want or need and then do it. I hope that helps what I perceive to be a problem.

Yes, you'll see us talking about the same sites over and over. There's some good stuff out there.

 

If you plan to use this unit for geocaching, the good news is this -- everyone is placing and finding by coordinates, so the fact that the map is sometimes in error should, at worst, put you on the wrong side of a creek now and then - but you'll still be looking where others were hiding.

[+keehotee]

All really good questions, and I appreciate the willingness to help me out. I just have the default map installed currently, the TOP U.S. 100K. I have no idea if its an auto-routing map. What I do know is that under ROUTING, I have Guidance Method set to Off Road, Lock On Road is No, Off Road Transitions is Auto.

 

I know there are probably a million posts on getting other maps, some of which I know can be free, so I just need to read through those threads and figure out what maps I even want or need and then do it. I hope that helps what I perceive to be a problem.

 

Forget the maps for the moment - how do the co-ords compare with those on your Nuvi? And where do they put you if you enter them into Google Earth or some other mapping software?

[+Bear and Ragged]

While 'setting up' the unit, check that it's set to the correct Datum -WGS84

[+ironmule2042]

Hey gang - I just picked up an Oregon 450T over the weekend and I've been really excited about the chance to use it. I got the batteries installed, started doing some minor config to the menus and did the electronic compass calibration. Imagine my shock when I let the satellites acquire and the map showed me on the opposite side of my cul-de-sac, about 300 feet away. I shut the unit down, powered it back up, and the same result. Today I connected it to the website, did the update, powered on/off etc, and it's still showing me on the oppposite side of my cul-de-sac. Has anyone else experienced this before? I'm really bummed and not sure what else to do at this point.

 

psubrian

 

I just bought myself the Oregon 450 myself. The first time I started it up mine too seemed to be a little off from what I expected. So I went back inside and downloaded a free topo map I found and installed that. The improvement on map accuracy was definitely noticeable. I'd bet it's the map and not the GPS that is your problem. Good luck. :-)

[+t4e]

 

If you plan to use this unit for geocaching, the good news is this -- everyone is placing and finding by coordinates, so the fact that the map is sometimes in error should, at worst, put you on the wrong side of a creek now and then - but you'll still be looking where others were hiding.

 

you make that sound as if its just a minor hassle, which can be true if the creek is dry or extremely low, totally different story if you find that out after hiking couple of kms on the wrong side and are faced with a raging creek between you and the cache...which would definitely not have you looking where the coordinates are

[+StarBrand]

Garmin's standard topo maps usually have the topo features pretty close to accurate but streets are sometimes horribly off - I've seen it numerous times in small rural towns.