Using Emlid Flow (latest version) for iOS. I noticed that the baseline field that is included in the CSV export shows a different length than the inversed length between the base and that same point. It’s around 1cm difference but if the baseline field is simply an inverse between the base position and all rover shots, they should be identical, right? Can someone test this in EM Flow for iOS? Baseline distance reported in CSV: 77.264. Screenshot shows inverse value. Perhaps it’s due to me keying in the base coordinate in local versus global? That shouldn’t matter, as it should be a 2D distance.
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Might want upload the exported csv? Wonder if a scaled factor is being applied?
Everything is in grid. I am seeing this behavior on almost any project. I guess I should ask the question… how are the baseline calculated between the base and Rover? Are these simply two dimensional grid distances? Are they geodetic ellipsoid distances? Or are they somehow ground distances? I am just trying to confirm that I understand how the baseline lengths are calculated and what type of distances those are. similarly, is the 2-D distance in the inverse command grid distance? I would assume that’s the case.
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If your using a grid system, you’ll get grid distances and grid bearing.
Your distance and azimuth willl be based on whatever system or projection used
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Can you upload the CSV file so we can see the columns etc.
2D distance I would assume means what is typically nomenclated as HORIZONTAL distance.
What is being exported as CSV may be Ellipsoid distance (geodetic) or Ground distance maybe depending on what columns you selected?
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Hi guys,
The baseline value is calculated as a straight distance between the base’s and the rover’s positions.
In the meantime, the result from the Inverse is based on the used projection and is grid distance. When using Global CS, the ellipsoidal distance is used as there is no applied projection.
Overall, this slight difference is expected, but it will not affect the accuracy of your surveys in any way.
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