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For planning bathymetry surveys line spacing needs to be 4x the estimated depth of the pond or lake you are surveying.
Which speed should I fly with the UGSC Echo Sounder?
Maximum speed should be 0.8...0.9 m/s. To collect high-quality data 0.7 ... 0.8 m/s
How do I maximize data precision with the UGCS Echo Sounder?
Echo Sounder should be fully submerged. You have too many spikes and gaps in the data. But I should tell you that the depth match on check lines is just perfect. That means that your approach with slightly submerged echosounder in case of calm water may allow to increase the speed of survey. Maybe you may experiment with just a slightly deeper echo sounder.
Should I use a single or double grid mission type?
It's almost useless to make a double-grid with an echo sounder unless you are trying to find some object on the bottom
Non-RTK Post-processing.
Data should be processed for the depth, not for elevation.
How do I import NMEA0183 into Hydromagic?
When you import NMEA0183 into Hydromagic, select SDXDR sentence to import both hi and low frequency data
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