Marine Electronics Reviews
IS Binocular, This is How We Test Them

Testing an IS binocular requires us to first get familiar with the controls and adjustments available on each binocular.

Then we head out to sea to test in daylight with a plan to stay until well after dark for nighttime testing.

At our first test site seas were running a close 2 to 3 feet. We setup so our deep-vee Contender test boat lay beam to. Under these conditions the deck was rolling hard with significant movement up and down.

We tried each binocular by looking across open water to a set of channel markers, first from a distance of 5000 feet to the closest beacon in the set and then from 1 nautical mile. The prevailing sea conditions and substantial deck movement proved to be an excellent way to test each stabilized binocular under extreme conditions.

To get some baseline results we took a pair of Fujinon FMTRC-SX 7x50 binoculars with us. We used these binos to see if we could read the channel markers from the same distances. Even our young eagle-eyed tester could not read the marker numbers with these top-quality but un-stabilized binoculars.

Next we moved into a channel with only a light chop on the surface and viewed a house about a mile down the shoreline. Here testers purposely leaned against the boat in an attempt to pick up some of the boat/engine vibration and transfer it to the binoculars. This site did well to show each binoculars ability to handle vibration and handshake.

Ratings on each image stabilized binocular is based on the observations of our testers. We examined each binocular for viewability based on results each achieved in daylight, at night, and from both test sites.

Focusing was reviewed too and reflects the usage of center focus and the right eye diopter, the usefulness of the diopter adjustment, and the comfort/effectiveness of the eyecups, both with and without eyeglasses.

A handling rating takes into account the quality of the supplied case, comfort of the neck strap, each unit's weight, and the shape and grip of each pair.

If a particular binocular performed well in all areas, it was rated highly. Deficiencies in one or more areas resulted in lower overall ratings.

Manufacturers' claims of waterproofness were confirmed by dunking each pair of binoculars in salt water, then rinsing them with a freshwater spray, followed by an examination for water intrusion. All the image stabilized binoculars we've tested thus far have passed this test with no problems noted.