Raymarine forum

Good day. I get these red “blocks” as shown in the photos on my FF screen each time I’m using rhe machine. This photo was taken in 4000’ of water, no other boats around and is typical. Transducer is a B744

Any idea what causes this?

Thank you

Hello Kingfisher,

You have Bottom Fill mode turned on. You're seeing this infill at times because the real bottom isn't in view and the system's thinking that the shallowest strong(ish) echo in view is the bottom - the systems always try to provide a depth reading for navigation purposes.

If you turn off Bottom Fill these blocks will go away.

Regards,
Tom