My question is how fast can i drive the boat(recommended) with sonar Lowrance Elite 7 Ti when logging in shallow lakes, the aim is to create maps with depth contour and bottom composition. (For information, maps should ba able to printed on paper and used when fishing)

The Lake have a deepest point of about 12m but average should be about 3-6m. Area of the lake are 11km2.

What distance should i use between tracks at 3m depth? 6m depth? and so on...

//Magnus

Use a spirit-level. Check it when going two knots and then start to increase your speed. When the level changes, you are going to fast so back off a bit. Usually that means a speed of 3-5 knots but it will depend a lot on your boat.

Distance between tracks is basicly up to you. In smal lakes I usually keep my tracks 30 meters or so apart. In larger lakes I will go up to 150 meters apart, look at the map for signs of interesting structure and then go back an map those areas with thighter tracks.

Thanks for the answer Colibri!

Its more about the angle of the transducer then the speed of the boat that decides how fast I can go with the boat when logging the lake! Am I right?

//Magnus

Up to a certain point Yes. At some point the delay in GPS-updates and the general processing done by the sonar will become a problem. The last part can to some extent be helped by reducing pingspeed (thus reducing the work done by the processor) and increasing the scrollspeed. But now we are wondering off into a subject where there is very litle documentation to relay on. :)