I have a echo map 93 sv and I have a LakeVu HD Ultra map chip. The lake I fish is supposed to have 1 ft. contours according to the specifications. So far I have not been able to find any 1 ft contours when using it on the lake. I was wondering if anyone could enlighten me on using this. Maybe I am doing something wrong. I have contacted Garmin support and they were not very much help. Thanks for any help