Context
Once you create your own layer, all calculated values from this layer are displayed in the Numerical information field. When the layer is selected (“activated”) in the Numerical information field (layer data shown with red text) or in echogram, all data shown by the relevant information fields are
calculated values from the echo data within the selected layer.
When a layer is established, it is drawn with two horizontal lines in the echograms. The lines identify the upper and lower
depth settings. If you have only one layer, it will always be "active", and shown with red lines. If you have more than two
layers, the "active" layer is shown with red lines, while the others are shown with black lines.
By default, a background layer collects all the data from the range chosen on the Main menu. Unless you specify your own layer(s), all data presented by the numerical information field are calculated based on the background
layer. This information can be more specific and accurate if you choose to specify layers in the water column.