Would this be visible at 2 nm?

[GordMay]

Originally Posted by a64pilot

I've got that lantern and it is bright, as in maybe like a 60W 120V light bulb bright...

FWIW: The luminous efficacy of a typical incandescent bulb is about 16 - 18 lumens per watt; hence the 580 lumen lamp would be roughly equivalent to a 30 - 40 watt incandescent.

[wrwakefield]

Originally Posted by dohenyboy

Coleman - LED Lanterns | Camp Lanterns | Coleman - Twin High Power LED Lantern

580 lumens appears to be as bright or brighter than the "certified" 2 nm anchor lights. Could run a 12v cord with it and hoist it with the jib halyard.
Or maybe lumens are not created equal? Not to suggest I would use this instead of a "certified" anchor light. I follow all government regulations of course, without question.
I do not see people on camping fora gushing about how fantastic marine anchor lights are for lighting up their campground.
But could be an inexpensive second light, closer to ground and easier for traffic to see.

Have you considered using these portable anchor lights?

cruisingsolutions.com/product/mega-bright-anchor-light/ [I have no affiliation; just a customer...]

I keep a couple of the 15 LED models on board (0.1amp) Plenty bright for an anchor light, and it lights the deck nicely too.

I've been using these for years (one each on fore and aft deck areas of a 50' sailboat) to supplement the 60 ft high masthead light- which isn't as helpful for close-quartered vessels...

[a64pilot]

Originally Posted by GordMay

FWIW: The luminous efficacy of a typical incandescent bulb is about 16 - 18 lumens per watt; hence the 580 lumen lamp would be roughly equivalent to a 30 - 40 watt incandescent.

Your right I'm sure, only thing is compared say to my Coleman 2 tube florescent, it is WAY brighter than that although the two tube is rechargeable and it's battery is a SLAB (sealed lead acid battery) and happens to be the one that is in a lot of Emergency exit lights, so it's easy and cheap to replace.
This thing if hauled 10 ft or so up my mast would I'm sure illuminate the whole deck well enough so that you could read a newspaper.

But, then so would an LED spreader light, and you don't have to haul anything up, all you would have to do is flip a switch

I'm all for being lit up, I'll never turn off my anchor light at night even if I'm in an anchorage that doesn't require it. I just think there are better ways to illuminate your deck than a battery powered lantern, although it is a great little lantern for grilling after dark, walks on the beach at night etc.

[hellosailor]

"lumens" aren't really a measure of brightness. You measure lumens by both the brightness and the area the light is covering. So, the same "bulb" with a beam covering a 2x2 foot area, four square feet, would be rated at 1/4 of the number of lumens that a bulb covering only one square foot is rated at.


if you don't know beamspread, lumens are deceptive and tricky stuff. I've got a small LED flashlight that's rated (ha) 2000 lumens. Well, sure, when the beam is focused down to a single foot square on the opposite wall. Open it out to 12' square...and the lumens plummets.


If I was a card-carrying cynic I'd say companies brag about "lumens" because no one can understand them and catch the deception. But I don't carry my card.


So take the lantern, hoist it, call someone who is two miles away and ask them if they can see which one it is. If they can SEE it, you just passed the USCG statutory requirement. Just remember, that requirement is a MINIMUM standard. Would you buy the minimum standard in a parachute?


Now call someone who is three miles away.(G)

[shipleft]

I would be real careful with that Jack, just because you can illuminate the deck with it , by no means does that give you the 2nm minimum required by law. That's why the lens is as important as the type and size of the light. If the freighter or supertanker only sees your camping lantern at 100 feet, do you think that is going to do you any good?

[shipleft]

Exactly! Maybe, none of these boats will ever find themselves in that situation where you are dead in the water at night, in heavy rain or fog, in a shipping lane and you are hearing that swish , swish , swish of a very large propeller, somewhere very close to you, but you aren't sure if they know you are there. Then the cost and inconvenience of putting up a proper light doesn't really seem like an issue.

[rwidman]

Talk about people getting carried away.

"Lumens"? "Luminous intensity"? "Pedanticised the whole anchor light rules"? "the cost of a marine part can be ten times the cost of a general use part?"

People, it's an anchor light. You go to West Marine or even Walmart and plunk down a few dollars, take it to the boat and install it following the instructions. Amazon.com will be happy to sell you any one of a dozen or more varieties.

Connect it to your boat's electrical system with a fuse and a switch and you're done. You're legal and you're relatively safe.

Why make such a big deal of such a simple thing?

http://www.amazon.com/Shoreline-Mari...ghts+for+boats

[Capt Phil]

Not certain how bright or how many lumens those old kerosene lanterns put out but we used them for years towing log booms down the coast in the PNW. Also used them for years as anchor lights. While small, they were cheap and denoted the last section of boom we were towing. You could see them for at least a couple of miles even in dark, rainy weather. Just drove a piece of re-bar into the last boomstick or swifter and went back in the skiff to refill the kerosene base every 3 days or so and gave the wick a bit of a trim. Never had another vessel run into the boom as far as we knew (but maybe it happened). Phil

[barnakiel]

I like boats that have whatever the requirement is and then a plain lamp somewhere so that a portion of the foredeck or the cockpit is lit too. I hope such an extra utility lamp is not against regulations. In any case, it helps me heaps when entering an anchorage in the dark.

b.

[conachair]

Originally Posted by hellosailor

if you don't know beamspread, lumens are deceptive and tricky stuff. I've got a small LED flashlight that's rated (ha) 2000 lumens. Well, sure, when the beam is focused down to a single foot square on the opposite wall. Open it out to 12' square...and the lumens plummets.

)

Suspect you've got that the wrong way round, lumens are how much, candelas are brightness. Sort of. A lumen focused on a single foot is the same amount as a lumen focused over 12 feet. Just not as bright.
Iprcs specs lights in candelas.

[roland stockham]

Yes, a battery powered lantern is a very useful emergency light strung in the rigging. I have certainly used one with a flat battery in the days when I sailed small engine-less boats! Also big lights show up well and camping lanterns tend to have a larger lit area. Colman lights are generally good quality and waterproof so last well on a boat (i have one that is well over 10 years old. All the stuff about masthead lights misses the point that an anchor light is supposed to be suspended in the fore triangle. The white masthead lights are often lost against the shore lights or stars

[Neptune's Gear]

I really don't agree with the must have upper and lower anchor lights theory. If your mast is 20m, and the other boat is 20m away, then the angle from them to the light is 45 degrees. That is roughly the limit of the human view WHEN LOOKING STRAIGHT AHEAD!!
So, the other helmsman does not have to look up, unless he is closer than 1 mast length. If he's that close, and not aware of you, he's not looking! If he's not looking, lighting won't matter!

[The Way]

Originally Posted by shipleft

I would be real careful with that Jack, just because you can illuminate the deck with it , by no means does that give you the 2nm minimum required by law. That's why the lens is as important as the type and size of the light. If the freighter or supertanker only sees your camping lantern at 100 feet, do you think that is going to do you any good?

You're right about that, of course. But I also use a masthead light. The lantern is mainly for close-in visibility.

I plan to row 2 miles away some day and see how visible the lantern is, but haven't done so yet.

Thanks for the comment,
Jack

[StuM]

Originally Posted by shipleft

Exactly! Maybe, none of these boats will ever find themselves in that situation where you are dead in the water at night, in heavy rain or fog, in a shipping lane and you are hearing that swish , swish , swish of a very large propeller, somewhere very close to you, but you aren't sure if they know you are there. Then the cost and inconvenience of putting up a proper light doesn't really seem like an issue.

What are you doing anchoring in a shipping lane in those conditions?

[FSMike]

Originally Posted by dohenyboy

My mast is about 80 feet high. and no wires in it right now. So installing a conventional anchor light will not be easy and will be very expensive.Considering the boat is not for cruising but only for day sails, and no plans to be out at night.. unless there is a problem. Its too small of a sailboat to live on for my tastes

You have a 74' Burger motor yacht with an 80' mast height? Could I possibly see a picture of that vessel?