Side-Imaging Today: The Humminbird 987c SI

Side-Imaging Today: The Humminbird 987c SI

Last year, Humminbird introduced a new type of sonar. Their high-end units now add Side-Imaging (SI) sonar standard color sonar imagery and GPS map navigation features. At roughly $2,000, the Humminbird 987c SI is about the most expensive sonar and GPS unit available. I find the SI to be a better searching tool than standard units.

Buyers gain a new search capability that simplifies the process of finding cover and structure likely to hold fish. The SI allows an angler to make passes down a shoreline or around important structures and mark spots as waypoints. The angler can then return to fish each waypoint to see if the spots are productive. Users more rapidly learn new waters and gain knowledge about underwater features they already fish.

Fish returns are smaller and more difficult to identify in SI imagery compared to standard vertical sonars. Schools of small baitfish appear as murky clouds rather than dark blobs. Fish the size of crappies or yellow bass may appear as small white dots, and individual gamefish like bass aren't much different than the returns created by stumps on bottom; but this is a cover-location tool, and effective use always has a learning curve.


Although gamefish and baitfish show as separate returns in SI imagery close to the boat, fish echoes farther to the side are mixed in with returns from the bottom and are more difficult to see. The clue that an SI return is a fish rather than a bottom or cover echo is a matching fish shadow farther away. Side imaging can help an angler locate and relocate moving schools of predator fish in relatively open water, but this is a bonus feature, not a primary benefit.


Beds of underwater vegetation are visible as marbled or bumpy bottom, but the soft edges of many submerged weedbeds may be indefinite. The prime benefit of SI is in definition of hard elements. Rockpiles and the deep edges of riprap are clear. Bridge construction and cover near pilings are revealed. Laydowns and underwater brush seen as blobs on bottom with vertical sonars become distinct logs and trees with defined branches. The clarity of various images recorded with the SI can be seen on the Humminbird website (humminbird.com). The increased fishing capability created by such detail is much like having photographs of exposed cover in a reservoir or lake.

Continued - click on page link below.


While the unit has many positive features, anglers should also be aware of its limitations. The SI unit's transducer must be located externally on the stern of a boat. The system works best at speeds under 10 mph and on straight-line courses, as turns distort the imagery.

How the stern is shaped and outboard motor is mounted influence whether the unit can "see" well to either side. Nothing may be placed in the line of sight to the sides of the transducer, and external mounting exposes the transducer to possible damage. Yet, I fish mine in Lake Fork, a water known for its hard-to-navigate stump fields, without damage.

I'm a beginner with the SI system and learn to better identify echoes and use other features on every outing. If you're a non-techie like me, you may find the complexity of menus and some options non-intuitive, but learning the details is rewarding. Users need to buy a map chip and may want another chip to record images for review with a personal computer.


Beyond conventional "fish-finding" sonars, the SI is worth the price if a user wants an advanced search tool.

Get Your Fish On.

Plan your next fishing and boating adventure here.

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Recommended Articles

See More Recommendations

Popular Videos

Portable Hornady Rapid Safes - Security on the Water

Portable Hornady Rapid Safes - Security on the Water

Hornady Security has a new line of portable safes with applications for anglers who want to have a firearm on board their boats, just in case.

Humminbird CoastMaster - A Closer Look

Humminbird CoastMaster - A Closer Look

Patterned after Humminbird's LakeMaster charts for freshwater anglers, CoastMaster charts bring the same features for salt anglers. CoastMaster delivers unrivaled nearshore and offshore fishing performance.

What

What's Next for ASA & ICAST?

American Sportfishing Association president talks ICAST, coronavirus and the fishing industry.

RIO Slickcast Fly Lines

RIO Slickcast Fly Lines

Chris Walker, with RIO Products, talks with Editor/Publisher Ross Purnell of Fly Fisherman magazine about the new SlickCast lineup of fly lines for 2020.

See More Popular Videos

Trending Articles

It was an August evening and I was wading the flats in Brewster, MA with my cousin. Here you can Other Fish

Must-Have Striped Bass Tackle

Rick Bach - May 04, 2017

It was an August evening and I was wading the flats in Brewster, MA with my cousin. Here you...

Several methods are available to estimate the weight of a fish. Some use length as well as girth measurements. Biology

Walleye Length To Weight Conversion Chart

Dr. Rob Neumann - January 03, 2017

Several methods are available to estimate the weight of a fish. Some use length as well as...

Catfish are simple creatures that can be caught using the best catfish rigs. Catching them is simply a matter of putting a good bait in the right in front of them. Catfish

8 Best Catfish Rigs - When, Where and How to Use Them

In-Fisherman

Catfish are simple creatures that can be caught using the best catfish rigs. Catching them is...

Their fighting ability is far superior to the largemouth bass—more par with muskies. Other Fish

The Case for Super Bass (AKA Snakeheads)

Steve Ryan - July 06, 2020

Their fighting ability is far superior to the largemouth bass—more par with muskies.

See More Trending Articles

More Accessories

Check out these top 2020 Father's Day Gift Guide picks for the fishing dad on your list. Accessories

2020 Father's Day Gift Guide

In-Fisherman Staff - April 22, 2020

Check out these top 2020 Father's Day Gift Guide picks for the fishing dad on your list.

A lightweight, wrap frame with the latest mirror color MAUIGreen. Accessories

Maui Jim Local Kline Sunglasses

Chris Schneider - December 04, 2019

A lightweight, wrap frame with the latest mirror color MAUIGreen.

Top professional bass anglers use underwater cameras to discover the Accessories

Pro Tips: Aqua-Vu for More Bass

Cory Schmidt - June 23, 2020

Top professional bass anglers use underwater cameras to discover the "lay of the land".

The Aqua-Vu Micro Revolution is a great solution for kayak anglers or smaller boats. Accessories

Aqua-Vu Micro Revolution

In-Fisherman Staff - May 28, 2020

The Aqua-Vu Micro Revolution is a great solution for kayak anglers or smaller boats.

See More Accessories

GET THE MAGAZINE Subscribe & Save

Digital Now Included!

SUBSCRIBE NOW

Give a Gift   |   Subscriber Services

PREVIEW THIS MONTH'S ISSUE

GET THE NEWSLETTER Join the List and Never Miss a Thing.

Get Digital Access.

All In-Fisherman subscribers now have digital access to their magazine content. This means you have the option to read your magazine on most popular phones and tablets.

To get started, click the link below to visit mymagnow.com and learn how to access your digital magazine.

Get Digital Access

Not a Subscriber?
Subscribe Now