Team Hruby Posted June 19, 2008 Posted June 19, 2008 I think I get the general idea, but here's what I don't understand. If you have to be moving at a pace of 2 mph for the GPS to register a location (at least my legend C does), how can it do an average? If the unit is in a static position, it should not be able to register a location. But if I'm moving, well, what's there to average, the location is constantly changing? Or do I need to walk in a very tight circle (which would feel rather foolish). I don't get this. Quote
+keehotee Posted June 19, 2008 Posted June 19, 2008 (edited) You don't have to be moving for your GPS to get a location - only for it to tell you the direction to another location (unless you've got an electronic compass built in) Your GPSr will be quite capable (subject to getting a clean signal) to tell you exactly where you are whether you're moving or not. But if you're not moving it'll be unable to update your position against your "goto" waypoint to tell you what way you need to be heading..... Edited June 19, 2008 by keehotee Quote
+Renegade Knight Posted June 19, 2008 Posted June 19, 2008 I think I get the general idea, but here's what I don't understand. If you have to be moving at a pace of 2 mph for the GPS to register a location ... You have to be moving for the GPS to know which way you are going/facing. It compares the last position to the current one. Without knowing which way you are facing/going it can't create a compass pointer to guide you. Averaging when sitting still is different. Then it's just like you would think. Take a buch of readings and calculate the average of them all to find the "most central location" of all those points. Quote
+infiniteMPG Posted June 19, 2008 Posted June 19, 2008 Averaging when sitting still is different. Then it's just like you would think. Take a buch of readings and calculate the average of them all to find the "most central location" of all those points.What I have sometimes fallen back on (this relates to hiding caches, not finding them) is take a bunch of readings, run back home and plop them in Google Earth, then zoom in as tight as I can and see which one "looks" like it's in the right place. You'd be amazed sometimes at where the readings show up when you do that. Sometimes on the other side of a fence or down in a river. Even Mr. Garmin has his bad days. This beats posting coords that are 50-feet off. And we've got a few around here that I have found and checked, double and triple checked and found they were over 125-feet off Quote
+J-Way Posted June 19, 2008 Posted June 19, 2008 Averaging when sitting still is different. Then it's just like you would think. Take a buch of readings and calculate the average of them all to find the "most central location" of all those points.What I have sometimes fallen back on (this relates to hiding caches, not finding them) is take a bunch of readings, run back home and plop them in Google Earth, then zoom in as tight as I can and see which one "looks" like it's in the right place. You'd be amazed sometimes at where the readings show up when you do that. Sometimes on the other side of a fence or down in a river. Even Mr. Garmin has his bad days. This beats posting coords that are 50-feet off. And we've got a few around here that I have found and checked, double and triple checked and found they were over 125-feet off Ummm.... you're assuming the images in Google Earth are more precise than a hand-held GPS? Those guys usually do a stellar job of putting the images in the right spot. But sometimes they're well outside the standard 10-30ft handheld GPS receiver deviation. I work on projects where the coordinates of points are determined by professional surveyors (precise to less than a millimeter) using redundant measurements from established benchmarks, or using aerial LIDAR surveys. Import these points (or LIDAR images) into GE and you might easily be on the "other side of a fence or down a river". But in spite of its limitations I agree that checking the coordinates in GE (or something similar) is a VERY good idea before publication. Quote
+hukilaulau Posted June 19, 2008 Posted June 19, 2008 But in spite of its limitations I agree that checking the coordinates in GE (or something similar) is a VERY good idea before publication. It's also a good idea to do this just AFTER you submit the listing to make sure you haven't typo'd a digit! Quote
+Renegade Knight Posted June 19, 2008 Posted June 19, 2008 Averaging when sitting still is different. Then it's just like you would think. Take a buch of readings and calculate the average of them all to find the "most central location" of all those points.What I have sometimes fallen back on (this relates to hiding caches, not finding them) is take a bunch of readings, run back home and plop them in Google Earth, then zoom in as tight as I can and see which one "looks" like it's in the right place. You'd be amazed sometimes at where the readings show up when you do that. Sometimes on the other side of a fence or down in a river. Even Mr. Garmin has his bad days. This beats posting coords that are 50-feet off. And we've got a few around here that I have found and checked, double and triple checked and found they were over 125-feet off J-Way's post not withstanding. You have hit the nail on the head as to why averaging doesn't really do much when it's over a short time. Your GPS can be very precicly calculating your position 30 west of where you are standing. An average would pinpoint that wrong spot. I still averge anyway. Quote
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