Jump to content

Projecting a waypoint......


garyo1954

Recommended Posts

In the field, I would use the waypoint projection feature of my geocaching app, or the one of my GPS receiver. Sitting at a computer, I would use one of the many tools that can do the projection and return the coordinates of the projected waypoint.

  • Upvote 1
Link to comment
22 minutes ago, niraD said:

In the field, I would use the waypoint projection feature of my geocaching app, or the one of my GPS receiver. Sitting at a computer, I would use one of the many tools that can do the projection and return the coordinates of the projected waypoint.

What is the waypoint projection feature in the GPSr? Where is it? Please.....

Link to comment
2 hours ago, garyo1954 said:

Thank you! Sadly, the Etrex 10 is not capable of projecting waypoints. Such is life! Another thing I learned today.....:D

 

Open the waypoint in waypoint mananger > Hit Menu button > choose "Project Waypoint"

Edited by HHL
  • Upvote 2
Link to comment

Another thing you should know is that with a Garmin you can only project in whole degrees.  At relatively short distances it's not a big factor but as an example, a half degree at 1600 meters is just about 15 meters.  When I have to do a long projection at fractional degrees, I'll convert the degrees to mils for better accuracy.

Link to comment
8 hours ago, HHL said:

Open the waypoint in waypoint mananger > Hit Menu button > choose "Project Waypoint"

Insane! I've never seen that menu! Looks like that is what I need.

 

 

1 hour ago, icezebra11 said:

Another thing you should know is that with a Garmin you can only project in whole degrees.  At relatively short distances it's not a big factor but as an example, a half degree at 1600 meters is just about 15 meters.  When I have to do a long projection at fractional degrees, I'll convert the degrees to mils for better accuracy.

Being off was a big concern. If I understand what you are saying a 5 degree swing would be about 150 meters over a distance of 1600? I guesstimated about 60 meters over 200 feet. Still its best to know these things before you go trekking out in a bunch of fallen trees with leaves strewn over the ground. Nothing like waking up a rattlesnake or a copperhead when they want to be left alone.
 

To that end a nice walking stick is a must.

Thanks!

 

Link to comment
14 minutes ago, icezebra11 said:

You can use the geocaching toolbox link and do some projections and then find the distance between the resulting coordinates.  I tried two projections with 5 degrees of difference over 1600 meters and the distance between the two projected points was 139 meters.

Yes, barefootjeff pointed me to the toolbox last night which confirmed my undoing. LOL

I will get back out and find it. Was hoping to work my way back to get the virtual cache and the mystery cache but it began sprinkling while I signed the second log of the day.

Link to comment

You can also crunch the answer in the field with a calculator and pencil and paper provided you know how many feet are in each minute of latitude and longitude in your area.  From the distance and bearing, you can calculate the north-south distance and the east-west distance relative to your starting point using trig functions. Then convert those to minutes and add/subtract accordingly from your starting point.  If you have a map of the area, you can plot the general location to find a good route.

 

And, yes, I did this once.

Link to comment
42 minutes ago, Joe_L said:

You can also crunch the answer in the field with a calculator and pencil and paper provided you know how many feet are in each minute of latitude and longitude in your area.  From the distance and bearing, you can calculate the north-south distance and the east-west distance relative to your starting point using trig functions. Then convert those to minutes and add/subtract accordingly from your starting point.  If you have a map of the area, you can plot the general location to find a good route.

 

And, yes, I did this once.

You're a better man than me Joe! If I tried that I'd have to take my ex. I can see how that would go....

She teaches higher math. There is a story she once had a class who was having problems understand plotting functions along X and Y coordinates. She took them to the gym, put masking tape on the floor, and they marched along the axis as she called out coordinates. (I think they gave her teacher of the year for that idea alone, but she is brilliant with math).



 

Link to comment
18 minutes ago, travelingsages said:

Is there a way to project a waypoint from within the geocaching app for iPhone?

 

Not the Official App, but others do.  Here's a Help Center article about it:

https://www.geocaching.com/help/index.php?pg=kb.chapter&id=106&pgid=820

 

The last time I needed to project a waypoint, it was 1/4th of a mile away, and I used the online Geocaching Toolbox from an Android laptop at a picnic table (I had to compile other formulas as well).  For less than 300 yards, I do OK using my Garmin Oregon and eye-balling it (you set it with a compass direction, kind of iffy for very long distances).  For a very short walking distance without obstacles, I can sometimes pace it out.

 

There's a nice App for iPhone called "Commander Compass" that can do it.  Watch the free app of the day sites, and you may get the upgrade for free.  I did.

Link to comment

Assuming the Official Geocaching Apps for Apple & Android are similar (I use Android), you can navigate to a projected point, as long as the 'source' waypoint is registered.

 

Set the source waypoint as the target of your search. Then, using the Ribbon Compass on the bottom of the app's map display or switch to the Compass Display by tapping the compass symbol on the top bar IN THE CACHE DISPLAY, NOT THE MAP DISPLAY.

 

Finally, wander around until you're the correct distance away, at the REVERSE of the projection, meaning, pointing BACK to the defined source point.

 

In other words, if you're supposed to project a point from the corner of the building at 90 degrees for 500 feet, then just go east until the thingy tells you that the original point is 500 feet away at 270 degrees!

 

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...