So I've had instances where I saw big schools of bait on SI but not DI, and that didn't make sense to me. I figured if SI picked it up, it must be in the same cone as DI, but this video seems to explain it pretty well. Most of you probably already understand it, but I fish shallow cover a lot and don't use electronics all that much so it was helpful to me, and maybe will be for others.

 

10:30 mark explains it pretty well.

 

 

Here's a graphic that shows it as well.