Hi, has someone more information about bottom classificaton peakSV,E1,E2

any technical information how to use the different topics and what to expect using the diffent sliders, scale and offset.

nice to have part of reefmaster, but without (indepth) technical background information riskfull

is it possible to write a E1 or E2 solution to a external file??

thanks for any information

regards Chris

Hi Chris,

There is quite a bit of reading around on the web that describes the idea behind obtaining roughness and hardness values from the first and second echo returns (E1 and E2). See for example here and here for an overview. The system we have implemented takes after the methods described by Kloser 2001.

PeakSV is a little different, in that it simply calculates the average maximum signal return value in the first echo return. This is the second choice "hardness" layer behind E2, and is provided for tracks that have not been recorded at a high enough range to include the E2 return (at least double the depth, plus a "bit").

It is important to remember that any hardness or roughness values are relative values only, and that even tracks recorded with the same equipment in the same waterway can produce differing results. It is possible to cross-calibrate tracks to some extent by using the multiplier and offset values - these simply move and multiply the returns by the set amounts. More serious bottom classification requires precise calibration of units on every survey run, and is beyond the scope of RM and the units that RM's users own.

We might consider an export for the hardness layer values that we calculate in a future update.

Matt