I have seen some pretty lucid down imaging pictures. I can find brush and fish with my sonar but DI seems to not help any. Brush does not appear any clearer and fish do not show up as white dots as they should. Here's some example pictures. Please help me out guys because I would like to utilize my down imaging. My unit is the 899 SI DI hummingbird unit.

Looks like bait

DI does a very poor job of showing a few fish. It will show larger bait schools and some larger groups of fish. DI and SI is much better for showing structure and bottom contour.

what setting are you using on your DI?

An Imaging pulse is very thin front to back so it is not on a subject very long.

A 2D pulse is a somewhat inverted cone shape and will detect anything within its coverage for a lot longer period of time. More time=more pixels lit up=more history recorded.

The spec coverage angle for 200 kHz is 20 degrees. That equals 1/3 the depth.
The spec coverage angle for 83 kHz is 60 degrees. That equals the depth.

The Imaging pulse is just a few inches from front to back.
If you want more pixels lit with Imaging, increase your Chart Speed and stuff will take up more screen space.

This is a large brush/log pile with the three technologies:






With Imaging, the size of the parts of a brush pile is what is recorded, not an exaggerated blob like 2D does.

One more thing, if you did not exchange the included Compact SI transducer for the HDSI, you can get sharper images if you do.