Auto chart mapping

I’m wanting to chart some residential canals and marshes in Florida. To chart them, do you need a map chip and zero-line card. I understood you could record 8 hours without a mapping card. Also want to map some strip mines back home. Not wanting to invest a lot heavier into Bird, as I am looking at switching to Garmin.

You can record up to 8 hours on the unit without a card like you said. Beyond that, you’d need to purchase the Zero Lines card. No other map chip needed.

I tried a little the other day. All I got was brown shadowing.