While the 798cSI is capable of down imaging, my experience with this feature has not been good. I installed the unit about 6 months ago and after many hours on the water trying every combination of settings imaginable, I simply can't "see" anything at all on the DI screen. The bottom contour matches the sonar screen, but above the bottom is simply blank. Even simulator mode gets the same results.
The SI feature is marginally better, but I find myself using the old 2D sonar after getting frustrated with these features.
The transducer is mounted on the jackplate with Transducer Shield and Saver hardware and the unit's software was upgraded.
Suggestions appreciated.
Gary