Quote Originally Posted by CrappiePappy View Post
(or are those "match" shaped images the dock supports/posts ?? And if so, why do they not go all the way up to the prop wash strip ??)

... cp
I would guess those are indeed the dock posts starting in the left water column at about the 18ft SI Range line ...

This would mean the dock was a little over 18ft from the xducer before the sound pulse actually 1st contacted the dock posts ...

Echoes of a vertical structure all the way to the centerline would mean the xducer would be right up against the dock posts = shorter distance to xducer ...

Rickie