“Multifunction display” grows in meaning with each new generation of marine electronics. Sonar functions now include traditional down-looking 2-D scanning with and without CHIRP, high-definition side and down scanning, live forward scanning, 360-degree circular scanning and a choice of frequencies to optimize each type for either maximum detail or greatest scanning depth/distance. Most units with Ethernet connections can also show radar scans and forward-looking infrared (FLIR) live video for extra safety when eyesight isn’t enough. They can also share readings with other displays in real time. Units can network with virtually any NMEA 2000 or NMEA 0183 sensor or device and with some engines to show data like RPM, pressure and temperature readings. Many displays can also control autopilots, shallow water anchors, bow-mounted trolling motors, and your boat’s stereo system. All these capabilities compete for the limited space on our displays.

Some capabilities can be combined to save space. Many units can overlay radar scans and weather information onto map and chart pictures. Some Lowrance units can show a combination view of a high definition sonar scan and a conventional 2-D picture. Still, many features must stand alone in their own display window. This requires using split-screen views and the smaller the display, the tougher it is to make out important details in each downsized window. It isn’t often practical to split a screen into more than four separate windows and that means each window is only about one-fourth the size of the full screen. This makes details difficult to see on a unit with a five-inch screen and it explains the popularity of new big-screen models like the Lowrance HDS Carbon 16 with 16-inch display. This monster can be split into four seven-inch windows, each window larger than a five-inch display.

A 16” display is about three time larger than a 5” display and much easier to see but it doesn’t necessarily deliver three times the detail. In fact, it may have almost the same horizontal and vertical pixel counts as the smaller screen. A display split into four equal windows is going to present each separate view with about half the display’s total vertical and horizontal pixel counts. This isn’t much of a problem because today’s bigger screens have generous pixel counts and it’s usually a simple matter to enlarge one of the windows to fill the whole screen if you need its full pixel count for maximum detail.

If I was buying a new boat today I’d probably finance a set of big-screen units as part of the rig to ease the budget bruise. Triton Boats is already designing bass boats that are ready to flush-mount the Lowrance HDS Carbon 16 at both the console and front deck and I expect other builders to do the same. Bigger screens are coming mainly because we need them. Information overload has become a hallmark of today’s marine electronics and the bigger the screen the better.