Measuring Distances From Caches

[+donbadabon]

There seem to be many puzzle caches that have you measure a calculated distance from several points, and the point where they all intersect is the location of the actual cache.

 

I have Mapsend Topo, but it does not seem best suited for this type of activity. I end up printing out the map and trying to use a compass to draw the circles. But this is prone to error, and doesn't seem very accurate.

 

I would think any program that would put range circles around an area would be great.

 

Any recommendations on a mapping program that does this, or on one that you use to easily display the calculated distances?

 

thanks

[+Hemlock]

GeoCalc

[Hogarth]

Has anyone used this program? It comes in the form of an EXE which ought to tell you something.

 

[+sbell111]

Has anyone used this program? It comes in the form of an EXE which ought to tell you something.

That it's a program?

[Keystone]

Just for the halibut, I decided to see what was fishy about GeoCalc.

 

Let's see... it was recommended to you by a Groundspeak volunteer.

It was written by a very well-known geocacher who's an expert at puzzle caches.

It is used every day by geocachers everywhere.

 

I'm no brain sturgeon, but from my perch, I'd have to say that your accusation that something's fishy has floundered.

[+mtn-man]

I might just have to hit you with an admin brick for that last post Keystone! My attempt to hit you might flounder though, and the brick might just hit me on the foot.

 

[+bigcall]

The biggest problem is figuring out what program they used.

 

There are a lot of different ways to calculate distances as I'm sure you are aware. Depending on the distances involved, each technique may give widely varying answers.

 

Based on the description, I'm sure Fizzymagic's program will produce a highly accurate answer over a wide range of distances. However, unless the puzzle creator also used the same program you'll probably get a different answer than what they intended. The degree of the delta depends on the distance. Over a fairly short range, the earth can be approximated as flat and UTM coords will work fine (a ~15.5 mile distance should be accurate to ~33 ft)

[+mtn-man]

Surface Distance Calculator

 

This is a utility that I use for what its worth.

[+Prime Suspect]

Forward Inverse

 

This is a free download from a company that makes software tools for cartographers. It's a windows version of a program used by the National Geodetic Service. It's got 26 preset ellipsoids to choose from, numerous precision settings, and 7 selectable output units. Input and output in degrees or gradients, and in decimal degree, degree minutes, or degree minutes seconds format.

 

You can give it two locations, and it will return the distance and direction. Or give it one position, and a direction and distance, and it will return the second location.

 

But be careful! It's an exe file!!!!!!!

Edited February 16, 2004 by Prime Suspect

[+9Key]

Prime Suspect wrote: Forward Inverse

You VB programmers stick together like Velcro!

[+fizzymagic]

Geocalc is open-source. I am happy to provide the source code to anyone who wants it. I just figured most people would prefer an exe file.

[Tahosa and Sons]

Try National Geographic TOPO, it can do distances and bearings. And gives coordinates also. And I find it useful for uploading waypoints into the GPS.

[+Teuchters]

Memory Map allows you to draw circles and then find out where they intersect. It is possible to set an "Alarm Radius" - something my GPS doesn't work with, but I presume some models buzz or ring when you get a preset distance from a waypoint. This is in the "Overlay" section. My pal Pharisee also has another method of messing with things like this - it's called AutoCad.

[+Prime Suspect]

Prime Suspect wrote: Forward Inverse

You VB programmers stick together like Velcro!

Well, I must say I admire their honesty. This is from their "ReadMe" file:

 

"Distribution of Forward/Inverse is an obvious marketing ploy to get individuals interested in geographic software to visit our web site."