Coords and map don't match

[Guest raptorrider2001]

What am I doing wrong? I searched for a cache near my zip code and printed out a copy . The coords were N33 2.306 W096 39.855. The map with the directions seem to be ok. When I enter the same coords in Topozone and on Jeeep.com, I get a location about 20-30 miles nw of where the cache is hidden according to the map on the cache page. I have tried converting the numbers and I still can't get it to match the map on the print out. I have tried this on several caches and get the same results. According to this, I would be looking in the wrong places if I used the Topozone map. But the Jeeep street map is the same as the one as the cache map. ???

[Guest arffer]

Looks like your working the 'Over The River..' cache id=1177

 

If the difference is 20-30 miles, it can't be a datum error. The co-ordinates you posted appear to be in decimal minutes format (dd mm.mmm), but neither topozone nor jeeep accept that format.

 

Both topozone and jeeep will accept coords in either degree/minute/second or in decimal degrees, but decimal minutes are not an acceptable input.

 

So:

>N33 2.306 W096 39.855

converts to decimal degrees:

2.306/60=.03843 so N33.03843

39.855/60=0.66425 so W-096.66425 (remember West = negative)

 

Entering these co-ordinates into topozone gives the same location as the cache map.

 

One final note: The spot displayed on topozone in this manner can be off by as much as 200 feet. Even clicking on the link to topozone from the cache page, which will use the same coordinates as calculated above, will be slightly off. The reason is that the coordinates displayed on the geocaching.com cache page are using WGS84 datum, and topozone uses the USGS standard of NAD27. There are a number of utilities, including your GPSR itself, that will convert between WGS84 and NAD27. My favorite is to use easygps (free).

 

[This message has been edited by arffer (edited 29 July 2001).]

[Guest raptorrider2001]

Thanks, you have been a great help. I guess I just have not paid enough attention to learning to recognize the different numbers and converting them right. Thanks again.