# Projecting Waypoints - Oregon 450t

## Recommended Posts

I am having trouble entering a bearing precisely. My Oregon doesn't seem to allow me to enter any degrees to the right of the decimal point. I want to enter a bearing that looks like this: XXX.YYY.

Is this possible?

##### Link to comment

Why would you want to? Unless you're projecting a waypoint to the moon (being extreme here...LOL) you SHOULDN'T need to be that precise.

##### Link to comment

@kurchian,

Go back over to the Oregon wiki and read the answer there.

##### Link to comment

You can always convert to mils, which are slightly more precise than degrees. But again, unless you're projecting really long distances (100's of miles), the difference between a single degree will likely be within your GPS's normal error range. So when you get into fractions of a degree, you're really pushing the kind of precision that even a fancy orienteering compass can't resolve to.

What you DO need to take note of when projecting waypoints is your north reference. If you're projecting waypoints from another user's directions, make sure you know whether that user is giving you directions according to magnetic or true north. If you're projecting waypoints for others to follow, be sure to note that in your instructions.

##### Link to comment

(100's of miles)?????? NOT HARDLY!

Calculate the error in feet in just over "one" mile. (or less).

And around here you've got whiners that complain about their GPS being "useless" if it can't "hold their hand" and "lead" them to within less than 10 ft of a cache.

##### Link to comment

(100's of miles)?????? NOT HARDLY!

Calculate the error in feet in just over "one" mile. (or less).

And around here you've got whiners that complain about their GPS being "useless" if it can't "hold their hand" and "lead" them to within less than 10 ft of a cache.

Ok, so maybe I was exaggerating a bit. At one degree, you'll miss your target by about 90 feet if your target is a mile away. So, at 1/3 of a mile, you'd miss your target by 30 feet, which is the accepted error of a consumer GPS unit. Therefore, unless you are projecting waypoints greater than 1/3 mile, or 1760 feet, then your bearing can be off by a degree in either direction and be just fine. Thus, fractions of a degree are nominal at most projection distances. Then again, if you're projecting waypoints more than 1/3 mile away, you might as well give coordinates.

##### Link to comment

@ mineral 2,

You are "preaching to the choir" here.....and you're definitely NOT suppose to use logic or common sense ! HA !

I think that some posters would only be happy if they could send their GPS out to find caches on it's own and have it bring back a list of what it found......

No, really, the OP needed to enter a bearing into his GPS that was given to him in decimal degrees.

For whatever reason I don't have a clue. I don't even care. Maybe it was for some special project where someone thought it was of infinite importance and required.

In another forum he was led to believe that it couldn't be done. I disagreed and told him how.

##### Link to comment

My Magellan SporTrak and Meridian will do the next best, XXX.YY

When the plat reads 4872 ft, 271.23 deg, I can project one point 271 deg and one point 272 deg, on my 60Cx, then zoom in on the Map Page, with both showing, and gustimate where the .23 is and make a point there. Then project in mils and see how close my guess was. Helps to be close when working in the mountains

##### Link to comment

I've seen lots of Geocaches that project over 20 km, especially old ones before the rule that the posted coordinates needed to be close to the final. With these long projection accuracy is very important. In fact, the projection method comes into play.

##### Link to comment

I've seen lots of Geocaches that project over 20 km, especially old ones before the rule that the posted coordinates needed to be close to the final. With these long projection accuracy is very important. In fact, the projection method comes into play.

Yep, I'm working on one like that now.

Tag is nearby with a set of coordinates, do some math with the coordinates on the tag, position an object pointing to true north, do a projection of the required degrees (as determined by a setting of said object) and a distance that is also determined by the value on said object and a fixed speed.

In the end, it was a 13.4 km projection and my result ended up on someones roof about a km short and several degrees off

##### Link to comment

I have the same problem as the OP, but I can't find the Oregon wiki or wherever I'm supposed to look up the answer. How do I enter bearings with decimal places in an Oregon 450?

##### Link to comment

You don't. However, as someone has suggested, a conversion from degrees to mils first will improve the precision since your mil entry on the 450 allows for a more precise entry.

As suggested above, whether the decimal degree entry is truly important depends a lot upon the distance to the target. What's the range that goes along with your bearing?

##### Link to comment

It varies. One recent geocache was 462 meters, but another one I haven't been able to find yet is over 5 miles.

I have to admit, I don't know how to use mils, or even what they are. One suggestion I thought might work was to put in two projections bracketing the degree. Something to remember next time I'm out in the field and I know "it's around here somewhere."

##### Link to comment

I've used GE when the projection is some awkward angle.

As for mils:

1 mil (the smallest number you can enter for those units) = 0.05625 degree, so you roughly double your precision using mils.

Still not great if the CO is calling for 238.3 degrees. If there's a significant distance involved, GE becomes by far the better tool for the projection unless you've got a good topo map handy and 'today's' declination.

##### Link to comment

Actually, I believe you meant to say ≈17.77777777777778 times and not double.

Path, just use FizzyCalc to accurately project your waypoint:

http://www.fizzymagic.net/Geocaching/index.html

Edited by coggins
##### Link to comment

Indeed, more on the order of 20X, not 2X. The 0.5625 remains regardless of the scale. Fouled myself up trying to reduce the 0.1 degrees he'd need to 1.77777 mils and then lost track of the decimal. Long day and haven't had to do it in the field for a while.

I prefer GE for really long projections only because it gives a good overview of the area of interest. I'll drop a point and draw a line.

Have had situations where bracketing (as mentioned above) was really helpful this way when the exact value of the bearing was a bit ambiguous. Had one cache where we were expected to do the projection off the barrel of a cannon. Miserable to do with a compass since the amount if iron involved ruined that (that was a surprise!), and not any easier with a GPS with an electronic compass for the same reason. We tried to back away from the metal and eyeball it, but we wound up with about a 1 degree +/- uncertainty at quite a lot distance. So drew the lines at the two extremes on GE to 'bracket' the area where we might want to look and wound up being able to draw a line about 200m long between the two endpoints. Fortunately, some of the solutions put us into a body of water, and that further limited the search area. Much of the rest of the area was scrub, so we focused on the few features (a guard rail on a road, a tree, and a bit of fence) to come up with the find.

If it has to be solved in the field, the use of mils gets pretty close. If there's time to sit down over a PC and sort it out, the GE solution allows time to figure out possible targets and methods of access.

##### Link to comment

If there's time to sit down over a PC and sort it out, the GE solution allows time to figure out possible targets and methods of access.

At the PC I use GSAK which allows me to put in decimal degrees for projections. In real life, in the field I've never DNF'd a cache after a projection. I was always "close enough" (within margin of error of the GPS).

##### Link to comment

Path, just use FizzyCalc to accurately project your waypoint:

http://www.fizzymagic.net/Geocaching/index.html

Can't. No cell service where I cache (usually). I have to go home to use the computer. Not practical when the caching area is 2 hrs up a mountain!

##### Link to comment

Path, just use FizzyCalc to accurately project your waypoint:

http://www.fizzymagic.net/Geocaching/index.html

Can't. No cell service where I cache (usually). I have to go home to use the computer. Not practical when the caching area is 2 hrs up a mountain!

Fizzycalc isn't an online tool. It's an app, but there is no ios or android version of it. There are, however, other tools for phones that do the same thing. No need for cell service.

##### Link to comment

Windows 10 Calculator App seems to be an upgrade from previous versions, and may be more precise than legacy computer or gps device map App projections.

##### Link to comment

Fizzycalc isn't an online tool. It's an app, but there is no ios or android version of it. There are, however, other tools for phones that do the same thing. No need for cell service.

Not having cell service means I also don't have a cell phone. I'm guessing apps don't run on an Oregon 450.

Edited by Path Pacer
##### Link to comment

It's an app for Windows.

## 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.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.