I have finished mapping a small lake and wanted to know if there was a way to define breaklines in my map? I have found the old riverbed and the contours are not generating properly in all the areas. I have done this with traditional land surfaces by creating breaklines - is there a way to do this in Reefmaster? My tracks are less than 30' apart along the river bed, so I hope that I would not need to obtain more data. The first attachment shows the tracks - the blue points are between 16' & 18' depth, but the 16' contour line does not generate properly through this channel attachment #2).

Any thoughts on this? Did I collect too much data and it is weeding out some of the shots?

Hey Ug, can you let us know what you are running at your interpolation at? from what you posted, it seems that you are mapping at a really small area. The general rule of recording is you can not have too much data. the more you cover, or record, the more detail you will have in your map.

Also keep in mind, if you recorded a sonar log with 30ft interpolation you will only have detail to that level. From your post it seems you are looking for more detail so, to me, you need to record a track right over the waypoint to fill it in even though your tracks are less than 30ft apart.

hope this helps bud.

I had interpolation set at 50m. I originally mapped the lake at a 50' grid. Once I gathered that data, I was able to determine the old creek bed and ran perpendicular cross sections at 50' feet apart between my original grid. I have toyed with the interpolation settings and the grid smoothing (both up & down) and it has helped some, but still not able to generate the contours properly. I think the only real way to get the results are to generate breaklines.

The attached screenshots show my original data, method for adding additional points along the river channel & the final results.

Here is my workaround for getting the contours to generate properly in Reefmaster.
1. Create a new waypoint collection.
2. Create new waypoints every place you want to add a depth point. Name the point the exact depth you want, so for 15' depth, name all your waypoints "15" (without quotes).
3. Export your waypoints out as a CSV file.
4. Import the CSV you just created as a track through the "Import GPS assets" tool.
5. Add the new track to your project.

This method is kinda tedious, but it is the only way I found to be able to accomplish this in Reefmaster without excessive data collection efforts or processing the data in another software.

Your tracks that run adjacent to the channel are closer to the crossing points (blue trackpoints) in the channel than the subsequent track (blue trackpoints) that crosses the channel, so although your eye can clearly see the pattern, maths cannot. You need to run along the channel, or cross it closer to the original crossing track a couple of times so that your "next closest point" is in or near the channel. Then your interpolation will work. Your fix is rather elegant though, although simpler ways are of course possible outside of RM (maybe even inside RM ? ) It would certainly be a very useful addition to the application to be able to create lines of "same depth" trackpoints by eye - sometimes maths simply isnt as good as the human brain at pattern matching.

T

Thanks for the insight AnglingCharts. Do you have a preferred method inside or outside of RM for obtaining similar results (without additional data collection)? I am familiar with land surveying and my other software choked (Civil3d) when I tried to import all the data I collected. Reefmaster has been great for quickly viewing & stylizing the data.

I guess once I start working with the data outside of RM, then there is no way to import the DTM back into RM.