First of all let me start by saying that boating binoculars are definitely different than the hunting binoculars as well as the general birding binoculars.

Features of boating binoculars:

A good pair of boating binoculars should have the following features and these are

Waterproof
 
Fogproof
 
Rugged
 
Preferably should have a compass
 
Image stabilization is a must – A lot of binoculars have the inbuilt gyro stabilizing system as the boating activity may involve a lot of adverse conditions. These binoculars are generally O ring sealed as well as these are nitrogen purged for the fogproof properties

Some the top rated boating binoculars brands are
 
Pro Mariner series
 
Nikon Sports and Marine Binoculars 7×50 with Compass
 
Nikon Binoculars Oceanpro
 
Steiner Commander v 7×50
 
Steiner Navigator 8×50
 
Steiner Military marine
 
Bushnell Binoculars marine center focus
 
Bushnell binoculars H2O series
 
Barska Deep sea binoculars

Best magnification for boating binoculars
 

The best magnification for the boating binoculars is 7. 7x is optimum for the boating ones as it has enough power for viewing. Higher power makes it tough for viewing.
 The marine or boating binoculars should be fully multicoated as well as they should have a good compass. To accommodate the compass the best design is the porro prism design.
 
Most compasses will get illuminated at night and that will be helpful as boating or marine activity can be done at night and it will cause issues if there is no light.

Field of view for boating binoculars

A wide field of view for boating binoculars is needed as you will be viewing an area which is big enough while on the boat.

Focus

There are different types of focus and for boating binoculars the perma-focus or auto focus binoculars are better than the individual eye focus.