Humminbird fish graphability

[zachp]

I have a humminbird 797 and it doesn't graph fish very well if at all...I have a lowrance 334 on the bow and it shows almost perfect arcs that make distinguishing fish and rocks and weeds very easy. I ran a test by watching both units simultaneously at the same settings, the lowrance graphed fish with perfect arcs 6" to 2 feet off bottom, it showed a school of baitfish with small arcs by it which were smaller perch feeding, the humminbird was showing small straight lines which didn't look anything like fish, it looked more like a small clump of weeds, and it didn't graph the school of baitfish that the lowrance did either.

Any thoughts? I have the sensitivity all the way up and chart speed up around 80%. It seems that even though the sensitivity is all the way it could still go up more.

The lowrance unit appears to be much better at showing bottom definition and differentiating between structure, as well as the fish graphing thing.

[hitthebricks]

Zach, I have the 979 and find that Huminbirds displays what is there alot different than my lowrance unit. I turned on the fish id to help with the learning curve and also sort through fish and random bottom debris. Their also is a forum on yahoo that is great for answering any questions you have about the Huminbird SI products. HTB

[Try Too Fish]

I am not familiar with your unit, but I have a 997 and in my opinion and experience with using Lowrance for years I think my Hummingbird is better! I wonder if there is something wrong with your unit or transducer? Or maybe the transducer need to be adjusted. Transducer angle does affect fish arc display!

Maybe you should call Hummingbird customer service and see about sending it in. Especially if under warranty!

Good Luck!

[zachp]

The transducer is mounted almost perfectly level on the transom, i checked it while snorkeling this summer. I might check with humminbird about sending it in, it seems to show very little of what is actually down there, it looks like the sensitivity isn't tuned right, with it turned all the way up i get no clutter, on the lowrance unit i can't go above 90% or i get way too much clutter. What are you humminbird users setting your sensitivity at? i know it varies from lake to lake, but i should be picking up more with it turned all the way up.

[Hookmaster]

I've had a 777c2 for a little over a year and it marks arches fine when boat is moving. I think the Humminbird's have better sonar than Lowrance. Does the 797 have the same mount as others? Maybe you can try a different head unit to see if it is the head or the transducer.