My brother and I bought a 797 a couple of months ago. We had the same problem with the picture. It was burred and grainy.The guys on this forum said to make sure we run a straight line,try to match chart speed to how fast you are running. It worked. They also said if we would just shoot one side and bring in the view to around 60 would get clearer and larger. It worked great for us. Hope this helps.When the president sends out his stimulas check I think we are going to upgrade tp the 997 for the console and 797 on trolling motor.