Below is a pic from a CBC news article of a Canadian sailor:
Am I wrong in thinking that any ship or threat that’s visible through binoculars would also have been picked up by radar, and at a greater distance? If so, what’s the point of ‘keeping watch’ with binoculars (especially when no threats are expected, i.e. not in a war scenario)?
I know this is FQ, but the photographer may have just asked for the sailor to “do something” for the picture and then the journalist may have just written a throwaway caption. I wouldn’t take this one picture as evidence that sailors spend any significant amount of time scanning the horizon with binoculars hoping to see something.
Could be a log in the water, or a swimmer. They are not just looking for ships that might be shooting at them.
And even then, a periscope might be hard to see.
I’m just here to admire the Canadian Navy’s grooming standards.
I went poking around on google, and apparently the U.S. Navy still uses binoculars.
Could also be a whale or a buoy.
I also found a Reddit post where someone in the Navy was complaining about how their ship binoculars sucked and was asking for recommendations so that he could buy a decent pair himself. A lot of the replies were that he should document the shortcomings and force the Navy to pay for it instead of paying to fix it himself.
You might want to see what people are actually doing on a boat. Like smugglers or if they are armed.
Or sunbathers. I would have thought that cameras would have made binoculars obsolete by now.
From the United States Navy Lookout Training Handbook (2000):
This rule is repeated in the current Amalgamated International & U.S. Inland Navigation Rules.
The Lookout Training Handbook devotes many pages to binocular use.
Radar can fail, or miss something significant (like, say, floating debris). There’s still no system better than human eyes and decision making.
Could be watching activities on deck that are at the far end.
Aha! Thanks!
The most common use for binoculars in my experience was to classify and identify precisely what the radar was showing you. Is that green blob on the radar a merchant ship, a warship, or an offshore oil rig? Does its aspect through the binoculars correspond to what the radar is saying as far as heading? Are there any day shapes hanging from the masthead?
And, yes, as noted, the old partially submerged log is something to look out for as well.
I would also note that one does not spend hours upon hours just staring through binoculars. Rather, one will devote most of one’s time to scanning the horizon with the naked eye, and occasionally referring to the radar screen (if one is at hand) and making quick sweeps of the horizon all around and in the direct path of the ship with binoculars.
The photographer here just chose to take a picture of the lookout as he was using binoculars, but the lookouts eyes were surely not glued to the binoculars the whole watch.
“Iceberg!! Dead ahead!”
All this fancy technology, but you can’t beat the Mk1 Eyeball.
Yeah, he looks a bit more like a pirate than a sailor in a nation’s navy.
I recall the joke where a USN ship radios for a RADAR contact to change course, and a guy radios back that he is in a light house.
Also the consideration that the sea is not always calm, so smaller targets - lifeboats etc. - may only bob into view occasionally, and similarly the vessel on the horizon will be obscured by the waves, you can only catch glimpses. In that case, binoculars help resolve those momentary views.
Sailboats and other small craft are pretty much invisible on radar
As stated above, radar is not good for spotting smaller craft on the surface. It’s more for large undersea obstacles.
Currents and even temperature can alter how radar responds. Visual contact is far more reliable.
Charts only tell you how the sea floor looked the last time somebody passed this way - if they are even that well updated. The sea floor can change dramatically with a single storm.
A well-trained and experienced look-out can read a great deal from the ripples and waves. They can tell what the current is doing, or what changes are coming up in the sea floor if it is shallow. They can predict a current about to push the vessel off course and advise corrections. Radar can’t see flow.
Lookouts are also watching local weather signs, which don’t always match the reports from the satellite level.
It’s a whole thing. Extremely important job.
Well, maybe with a Mark-1 eyeball and a pair of binoculars. 
? Radar can’t see anything under the water.