The Lowrance Mark 4 HDI comes with a 4.3 inch greyscale screen. HDI stands for Hybrid Dual Imaging and provides both the Broadband Sounder and DownScan. HDI was first introduced by the Elite7 model and it provides extremely accurate fish markings and is capable of tracking bait movement. There is also Downscan Overlay that allows users to combine Downscan Imaging view with the Broadband Sounder. The resulting display separates fish targets from the surrounding structure and vegetation. It allows for full adjustability of the overlay.
Lowrance’s Advanced Signal Processing (ASP) maximizes fishing time by reducing the need to manually adjust settings to see fish, structure and bottom detail more clearly. Exclusive TrackBack functionality allows anglers to scroll back in recorded sonar history to review structure, transitions and fish targets, and pinpoint locations with a waypoint (on chartplotter models) — eliminating the need to circle back and retrace their path.
Another plus to the Lowrance product is chartplotter capability. They include with this an accurate built-in GPS antenna and a detailed U.S. map. There are more than 3,000 lakes and rivers, and coastal regions that reach to a depth of 1,000 ft. The Mark 4 HDI is compatible with Lowrance’s online map creation service – Insight Genesis. This allows anglers to create custom, high-resolution bottom and vegetation maps from recordings you make on your own excursions.
Even though Mark 4 HDI is very affordable, it has most of the bells and whistles of the more expensive units. It is best for inland fishing reaching a depth of 1,000 feet. You can find the 50/200 kHz Skimmer transducer as an optional upgrade. That transducer reaches depths of 2,500 feet. The maximum depth for DownScan is 300 feet.
The Mark-4 HDI does come with a one-year limited warranty and their exclusive Lowrance Advantage Service program. This model ranges in price from $149 to $329. Lowrance Mark-4 HDI may be ideal for the beginning angler, or the advanced fisherman who simply wants a bit of an edge over their own instinct. You can get a great deal on Lowrance Mark 4 HDI here.
| Lowrance Mark-4 HDI | Humminbird 581i DI | |
|---|---|---|
|  | |
| Screen Size | 4.3 in | 5 in |
| Screen Resolution | 480 x 272 pixels | 640 x 320 pixels |
| Display Type | Monochrome TFT with 11-Level LED backlight | 16-level grayscale |
| Imaging | 2D, Down Imaging, Downscan Overlay | 2D and Down Imaging |
| Transmit Power | Max 250W RMS, 30,000W Peak to Peak (analog equivalent) | 300W RMS 2400W Peak-To-Peak |
| Sonar Frequency | 83/200 kHz 2D 455/800 kHz Down Imaging also 50/200 KHz dual frequency transducers | 200 kHz 2D Sonar 455/800 kHz Down Imaging |
| Maximum Depth | 300 ft Down Imaging 750 ft 2D @ 77 kHz 2000 ft 2D @ 50 kHz | 250 ft (DI), 600 ft (2D Sonar) |
| Waypoints Storage | 3000 | 2500 |
| Routes | 100 | 50 |
| Trails | Up to 100 trails - up to 10,000 points / trail | Up to 50 trails w/20,000 points each |
| Map Compatibility | Lake Insight and Nautic Insight PRO and HD, Navionics Gold and HotMaps Premium, Fishing Hotspots PRO and Jeppesen C-Map Max-N. | Fishing Hot Spots, NauticPath & Navionics (Hotmpas, Premium and Gold) |
| Background Map | US map with over 3,000 enhanced lake maps with depth contour and shoreline detail, plus coastal depth contours/shoreline detail and spot depth soundings to 1,000 ft./305 m | Humminbird UniMap |
| MSRP | $229 | $299 |
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| Review | Review |