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Qimera distances are always grid distances #31

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lindsaymbc opened this issue Mar 25, 2023 · 0 comments
Open

Qimera distances are always grid distances #31

lindsaymbc opened this issue Mar 25, 2023 · 0 comments
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bug Something isn't working data processing qimera

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@lindsaymbc
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Distances in Qimera are grid distances in the project coordinates, and not true distances. This may not be a problem when in a small survey in a UTM projection, BUT it's a significant problem if you are in World Mercator projection at 52N ... or anywhere not on the equator.

This applies to all distances shown in the profile tool (2D, 3D, surface), the measurement tool, and swath extinction plot (swath angles incorrect). The NOAA export csv of line statistics is also based on the projection; average line heading is grid heading, line distances are grid distances and not sure if calculation of average line speed in knots is correct.

There are issues raised with QPS support for the error in the swath extinction output and to better support geographic coordinates and will post any updates here.

@lindsaymbc lindsaymbc added bug Something isn't working qimera data processing labels Mar 27, 2023
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bug Something isn't working data processing qimera
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