I am going to be using the newest model of the Helix to map various rivers with side-scan, sometimes up too 100 km of river will be mapped. I am probably going to break them down in to smaller sections to keep file sizes manageable but I was interested in what SD cards I can use. Any recommendations would be helpful, I would like to be able to use the largest available memory and highest write speed cards but I have heard that the units have some limitation on what cards can be used. Also if anyone has experience mapping large areas and could reference about how much space these files usually take up that would be extremely helpful.
Thanks in advance.
RG