The more I use my Raymarine fishfinders and C-MAP cards, the more I appreciate how high-resolution hydrographic charts and CHIRP DownVision technology really work hand-in-hand to help me locate fish holding areas.
If you look at the screen-grab above you can see the detail on the C-Map chart on the left side of the screen. The weeds and weedlines are clearly marked. On the right side you can see the confirmation of exactly where the weedline ends. Using this technology for fishing really takes the guess work out of finding fish holding areas!