Garmin 60CSx map

[testrada]

Hi. New to this forum.

 

I was hiking today in an area I am very familiar with and noticed a disturbing problem with my garmin 60CSx.

It displayed my position way off on the map (or the maps is off of the coordinated position). I used a street as reference, which it showed me just passed the street on the gps, yet I was at a position in the trail easily 500-800 feet away from the street. It was about 21 degrees Fahrenheit, which is within its working specs.

 

This is disturbing because now I cannot trust the GPS with my location if I am in an unfamiliar or unknown location. When I got home, I downloaded the gpx track and displayed in google earth. It displays properly in google earth, which tells me that the coordinates are correct and the map is either wrong or offset in relation to the true coordinates.

 

Map loaded is from MapSource version 6.12.4, Topo US 2008 data set version 4.0

I tried reloading the map to the GPS and same issue.

The tracks over imposed on the mapsource map on the PC are also offset

The tracks over imposed on google earth are correct.

 

The area in question is Nashua, NH, and the trails is within a city park.

 

Anyone experienced this before? Any solutions, advice greatly appreciated

 

Thanks!

Tony

 

PS - sorry about the title of this post, I meant to say Garmin 60CSx map offset from coordinated position

Edited February 2, 2009 by testrada

[+vwaldoguy]

I've read other posts on this that the Topo 2008 maps are not the most accurate maps out there for roads. And, I've observed that myself to some degree. The distance from the road can be pretty deceiving too, based on the zoom level that you've set, that if you are zoomed far out, a distance of 500/800 feet might only be a pixel or two, but if zoomed in close, could be the difference of a whole screen.

[+Red90]

The roads on the map are not always accurate.

[testrada]

The roads on the map are not always accurate.

 

Thanks for the replies

I did some more testarch and many people having similar issues with topo 08

What baffles me is that of is not just the roads but also the bodies of water, elevation changes and all reference items displays (the entire map is offset by about 800 feet)

[eaparks]

Welcom to the forum testrada, I was curious about your encounter so I looked at my Garmin maps for Nashua and assume you are talking about Mine Falls Park. If this is the correct park, the trail loops (2) are on my U.S Topo v3.02 (version just prior to Topo 2008). I traced the trails in topo creating a track and viewed it in Google Earth. The topo track appeared to overlay the trails very very closely when viewing in Google Earth. I'll be glad to send you the traced track from Topo v3.02 if you want to compare to your Topo 2008.

 

I too, have seen instances where Topo is off on both trails and roads as much as 200-300 feet but not the 500 or 800 as you encountered. I would tend to believe the 60CSx is working properly and the unit may have accidentially had a button pushed without you realizing it and the map screen didn't move with you as you walked. Sometimes at a quick glance it is easy to mistake the arrow as being one's position as opposed to the solid black triangle, especially when you didn't knowingly move/toggle the arrow. This could easily give you the large error you thought you were seeing. This may not be what you experienced at all, just thought I'd throw it out as a possible scenario.

 

By the way, Mine Falls Park looks like a beautiful park from the pictures in GE.

[testrada]

Thanks for the reply.

It was not at Mines Falls - which is very beautiful in the middle of the city.

It was just a bit south west off Mines Falls, in a large area of land that the city bought back in 2000 from what was then known as Yudicky farm.

Here is the location:

http://maps.google.com/maps?f=q&source...mp;t=h&z=15

 

The GPS showed me as crossing right through the circling Tanglewood Dr. street, when in reality I was in the woods west of that.

 

So, for now the GPS is only good (trustable) for bread-crumbing your way around :-) granted, I am not an experienced GPS user, so I am still experimenting

 

Thanks again

Tony

[+StarBrand]

Not uncommon for TOPO to have road errors of a few hundred feet - 800 seems like a bit much. Terrain features are usually pretty close though.

[+OienLabs]

Wrong datum? (WGS84)

[testrada]

Not uncommon for TOPO to have road errors of a few hundred feet - 800 seems like a bit much. Terrain features are usually pretty close though.

 

Correction on my part -

 

Just checked the mapsource against the google maps terrain and it matches pretty well - looks like it only affects certain roads and not all elements on the map. That's a relief.

 

The terrain contour appears accurate (or at least matches google maps and mapsource). The road I am using to compare (where I had been hiking testing the gps) was recently built (about 2002) and is way off ( Tanglewood Dr, Nashua, NH ) by about 1000 feet comparing the diffs between mapsource vs google maps

 

http://maps.google.com/maps?f=q&source...mp;t=p&z=15

 

Ok, just wanted to clear this up for future searches

Thank you all who responded

 

Tony

[+JSWilson64]

Are you sure your datum is set to WGS84?

 

What about "lock on road" ? If you're on a trail, that should be "off".

[snowfleurys]

Check the gpsfiledopot for a recently finished custom topo map of NH.

 

Topo2008 is a 100K scale map. If there source data was Census Tiger files, over 1/3 of the counties had not undergone realignment, and many of the roads were more pictorial than actual location.

[testrada]

Wrong datum? (WGS84)

 

No, Map Datum is set to WGS 84 which matches the map.

It happens to be that one circle street which is off in the garmin topo 2008 map

I compared that street location with google maps and also with mapquest and the mapsource (topo us 2008) is much off, but just that street afaik.

 

http://maps.google.com/maps?f=q&source...mp;t=h&z=15

 

every thing else matches so it looks like it is just street issue - and it is about 1000 feet off when compared to google maps (so my 800feet estimate was close) :-)

 

thanks

tony