I found a Cache at location 1260,917

From 1059,1073 distance was 2609.03m (I have 100+ % Accuracy); This location is relatively higher than the cache.

Computed 2D distance between 1059,1073 and 1260,917 is 2544.35 m a 64m Delta

From 1197,849 distance was 927m

Computed distance between 1197,849 and 1260,917 is 925.52m a 1.48m Delta

This scan was obviously close, and made from a relavtive position 'below' the cache.

The other difference is scans were made with 5k and 1k loads.

Just to mix it up, a third scan was taken at 'about' the same vertical height;

969,1146 Distance given 3764.91m Calculated distance: 3704.24m 60.67m Delta

From above: 64 m 5% Difference between calculated and displayed
From ~same: 60.67 m 2% Difference between calculated and displayed
From below: 1.47 m .2% Difference between calculated and displayed

Each Tile is 10m from center to center. When measuring from tile 1,1 to tile 1,2, you'll get 10m, but from 1,1 to 2,2 you get 14m.

The further away, and the greater the 'angle', the higher the error.

This is proven out with one last scan, done at

976,915 (which is almost directly along the 'y' axis at the same elevation as the 927 m scan)
Displayed distance: 2834.66 m Calc. distance 2840.06 m which is only a 5.34 m delta and again a .2%

So two scans from the same elevation have the same % difference...

The conclusion... 'Z' may play a role in determining the Displayed distance, as the % difference did change with changes in elevation, but remained the same when repeated from the same elevation.

Why I say 'may' is that the 60ish m from the same level should'nt have any % difference if the ONLY thing was Z.

I think the 'angle' of incidence also adds error, as the 'same level' scan was done at about a 45 degree angle the grid. If you stand in one spot, and click around you, you'll see that you get a 9-10m reading from tiles 90 degress to the grid, while at 45 degree's you get 14-15m; which is correct as it's displaying the hypotenuse from center-center.

In the end, even with 100% accuracy, you need to seperate your scans by at least 10% (20% would be better) off the originally displayed value if you are trying to triangluate.