Page 3 of 5 FirstFirst 12345 LastLast
Results 21 to 30 of 46
  1. #21
    VicS is offline Registered User
    Location : Home: Kent. Boat: Chichester
    Join Date
    Jul 2002
    Posts
    31,632

    Default

    Quote Originally Posted by noelex View Post
    If you do the calculations a minimum of about 8 of the best quality 5mm LEDs running, with regulated circuitry, at peak brightness, are required to meet the visibility requirements. Bebi put 15 LEDs in their owl anchor light and their web site contains details of some calculations.
    So Lidl's statement that each LED has a brightness of 26,000 mcd must be wrong?

  2. #22
    Join Date
    Mar 2002
    Posts
    3,080

    Default

    We use a couple of them on stern and in front of the mast when anchoring. Fine I think until about 2 or 3 in the morning, and where we sail in the Med nobody enters anchorages more than a couple of hours after darkness. Without any lit bouys to guide you then it would be a bit foolish to enter in full darkness.

    Anything is better than a light up in the sky.

    it's on my list to get a 12v light on a lead to use if I'm ever in an anchorage with bright shore lights or where people are likely to enter in the predawn hours.

  3. #23
    Join Date
    Feb 2009
    Posts
    943

    Default

    I entered Cawsand bay late on a moonless (misty) night last Summer when there were quite yachts with anchor lights (anchored or on moorings it seemed). I'd never been there before so was trying to work out the lie of the land and the anchored yachts. Masthead anchor lights were **** as it's difficult to relate them to where the yacht was underneath. Garden lights were equally **** as they were just indistinct points of weak light that gave no sense of distance. The best were the ones that shone out as well as down illuminating some of the boat. In other places (maybe) masthead lights are better, I don't know (this was hardly a scientific test) but an anchor light that is bright enough to light up some of your deck makes it much easier for other people to judge distance and orientation of your beloved. I cannot see the point of using garden lights as anchor lights, they're just not bright enough especially when the batteries get old.
    Last edited by aslabend; 07-04-12 at 15:43.

  4. #24
    Join Date
    Feb 2010
    Posts
    13,049

    Default

    Quote Originally Posted by VicS View Post
    So Lidl's statement that each LED has a brightness of 26,000 mcd must be wrong?
    It may just be an optimistic measure of the output from the LED (which will have a narrow spread) rather than the all round brighness of the light.

    I've never seen a garden light which was clearly visible at half a mile, yet alone at four miles.

  5. #25
    pappaecho is offline Registered User
    Location : S. Hampshire
    Join Date
    Oct 2004
    Posts
    1,837

    Default

    A member of our club uses one with the following caveats.

    Firstly he replaced a 600 ma rechargeable with 2000 ma.

    Secondly he switches off the lamp with the switch provided when on the club moorings and only uses when at anchor. This means the battery is fully charged and thus last through the night on full power, even in the winter.

    he does not anchor for more than one night so limited repeat capability
    Def: Yachting - a way of spending the kids inheritance

  6. #26
    Join Date
    Jul 2005
    Posts
    2,069

    Default

    So Lidl's statement that each LED has a brightness of 26,000 mcd must be wrong

    That is not enough to meet the requirements. 5mm LEDs only have an output of about 20 degrees. A fresnel lens in the garden light is often used to extend this to 360 degrees, but the intensity is reduced as the light is spread out over a larger area.

  7. #27
    VicS is offline Registered User
    Location : Home: Kent. Boat: Chichester
    Join Date
    Jul 2002
    Posts
    31,632

    Default

    Quote Originally Posted by noelex View Post
    So Lidl's statement that each LED has a brightness of 26,000 mcd must be wrong

    That is not enough to meet the requirements. 5mm LEDs only have an output of about 20 degrees. A fresnel lens in the garden light is often used to extend this to 360 degrees, but the intensity is reduced as the light is spread out over a larger area.
    Yes thats the conclusion I was coming to.
    If each LED was directed around 180, the vertical spread not increased and there were no no losses the visible range would be reduced to something between 1 and 2 n.miles at best.

    It might still be fairly conspicuous at a few boat lengths. Useful perhaps to mark the boat on its mooring.

    The one I experimented with had a single LED shining downwards on to a domed reflector. Once the reflector was replaced with a conical one it was pretty obvious in the garden even from a lighted room.

  8. #28
    Join Date
    May 2009
    Posts
    145

    Default

    Has anyone just put ordinary AA batteries in them,higher voltage may mean their brighter.

  9. #29
    VicS is offline Registered User
    Location : Home: Kent. Boat: Chichester
    Join Date
    Jul 2002
    Posts
    31,632

    Default

    Quote Originally Posted by peteK View Post
    Has anyone just put ordinary AA batteries in them,higher voltage may mean their brighter.
    rather defeats the object of them being solar powered.

  10. #30
    Join Date
    May 2009
    Posts
    145

    Default

    Also overcomes the problem of keeping them in a locker and finding them not charged.
    Thinking of getting a card of batteries from the pound shop and they might last all night and not fade in the early hours.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •