fish or swim

I have the Hummingbird with side scan it works great for seeing bait. Get into water that doesn't same to have much life in it like Lake Huron. The regular fish finder doesn't have any thing on the screen, high end Furuno. Maybe the bait is scared away from the boat? And the regular Hummingbird view doesn't have anything on it but the side scan will often show plenty of bait. Using the side scan seems to have a tough learning curve but once it's working good and know what is on the screen it works really good.