Quote Originally Posted by callshy View Post
I have been through this several times with my dad and it took sitting down and drawing a picture for him to comprehend. Let's ay you have a 18' boat, transducer on the back and GPS on the front (does not matter if you are using side imaging or bottom scan). If you come across something and your transducer picks it up, by the time you hit the mark button on your unit you are at least 18' off since your GPS is on the front of the boat. Maybe that makes a little since. This is how I have looked at it anyway. When I first got the side imaging I noticed that I was always off to one side when I marked soemthing, this was due to the location of the transducer and GPS.
My sonar and gps are on my bow, on the trolling motor. I dont see the same point that you do. When i mark something on my unit, it's right under me not 16 or 18 feet behind me. I wont mark something if i'm moving away from it. I'll throw a marker out and go back to it then mark it. I see where you guys are going wrong. I know how to use my gps to put me on my spots. Maybe, if you're having a tough time with your way, give mine a try. 95% spot on when i mark it from my trolling motor.