Quote Originally Posted by kosmo View Post
ok,heres a picture showing humminbird true di and humminbird conventional 2d coverage area . at 100 feet the coverage area of humminbird 455khz true di is 153 feet. a fish could show up on the screen appearing to be beneath the boat when in reality it could be anywere left or right up to 76.5 feet to either side. humminbird conventional 2d sonar using 455 16 degree cone angle would only show fish in a coverage area of 28 feet at 100 feet. thats only 14 feet to either side.fish showing in the di coverage area past that will not show on the 2d. this is the way that i interpret richards theory anyhows.
Looks like you have it right Kosmo. I normally fish 12 foot or less 90% of the year, so I've never really struggled with where something is. If it's a point of interest, you'll normally hover around it anyway and pick it apart. To me DI can tell you if it's worth hitting, because you're able to know exactly what it is at first glance.

Sorry about the off-topic DG.