Only "settings" I'm aware of on a DI is 455mHz or 800mHz. 800mHz gives you a 45deg beam & 455mHz gives you a 75deg beam. The total swath of a 800mHz beam is 0.83 x bottom depth ... 400mHz is 1.53 x bottom depth.

I use 800mHz & fish in 20fow ... knowing that my beam swath is ~16ft wide. (or ~10ft wide at 12ft depths). I also get a clearer image.

Do I know which "side" of the boat the image is coming from ?? No, not really. But, I do know that it has to be within the limits of the beam swath, in accordance with the depth of water I'm in.