Just get record from Lowrance and TM150,(IG don't work with chirp fréquencies) firts cone angle change not possible to know it!
Record I get is in a lake 0 to 50m meters deep, in that record I have many faulth detph near 800 to 900m!!!
Need to corret a lot!
Best is to use on a single fréquency for cone angle!
I havn't use on botton composition (I havn't that module, I use RM for salt water and use more side mosaic), the lowest fréquency can be better for that.
For next record can do it with chirp at 42kHz and at 210kHz at the same time (I have 2 channels)to see if it change something on a place that I know by diving.