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Thread: Selling: Safety scan lens and mount

  1. #1
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    Default Selling: Safety scan lens and mount

    I won a safety scan lens and mount at SELEM this year which I don't have a use for.

    Send me an offer and which lens you want. I still need to contact them to let them know which one I want, so I can select whatever setting lens you'd like.

  2. #2
    Bradfo69's Avatar
    Bradfo69 is online now Pending BST Forum Purchases: $47,127,283.53
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    If no one else makes you an offer in a few days, I will. I'm not going to jump on it just yet because I have 7 lenses and 7 mounts and others that don't have a safety scan lens ought to consider one. The determination of what one to get is tricky.

    What I need to do though, is swap out some of my lenses with Pangolin if possible. I got all -6 diopter figuring it's the "safest" and it truly makes the show unwatchable at my distance and power. It's simply awful so, I have about $600 in lenses I can't use. If I end up making you an offer on yours, I think it would be a -3 or -4.

  3. #3
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    Brad, what distance and power are working with?

  4. #4
    Bradfo69's Avatar
    Bradfo69 is online now Pending BST Forum Purchases: $47,127,283.53
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    I put them so far on two Pluto II's rated at 2.5 watts and I'm typically viewing from roughly 90 feet away. Sometimes a bit closer but generally around 80-90 feet. At that point the beam is diverged to where it's about the diameter of a soccer ball. When it passes over your face, the resulting time it takes to cross your field of view is like being shined in the face with a oncoming car's high beam headlamp. You can't see the beams overhead because you're wincing and turning away from the damn "spotlight". The laser power may be very, very, diverged and safe but it's still too bright to watch.

    I've seen a show with the correct safety scan lens and it is a much more pleasant experience. I mentioned it to Bill at SELEM and he agreed that -6 under those conditions was a poor choice. Again... not knowing any better, I went with the most divergent thinking that it was the most "safe" and... I might use as many as 7 projectors at once so, went 7 lenses rather than 7 kits of 6 that contained all of them. I can't put out that kind of money for an effect I can't legally sell (audience scanning). I got them primarily for personal use and for LEM's.

  5. #5
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    hmm if you have smth like 4mm waist and 2.5W beam, then 90 feet (=27m) with -6 makes your beam 650mm wide 1,9mW/cm^2 dense (counting top-hat beam, with no respect to beam divergence). That is indeed a poor choice. You'd probably need to go with -3 at most (324mm and 7,6mW/cm^2 @ 90ft). With respect to divergence (lets say 1mrad) cuts density to 6,5mW/cm^2. And yes, sorry, I prefer SI units

    Though that's just theory, I don't have my safety kit yet, but I'm thinking about building it at the moment. So I'm wondering how does this look like for real.

  6. #6
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    Item Sold
    Payment and shipping complete
    Last edited by icecruncher; 09-07-2014 at 18:08.

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