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  • means what?

  • Has anyone got lights with a high beam strong enough to melt off people's faces yet? Not figuratively, literally melt off their faces. I pay top dorra.

  • How does the screeching authority minimize the humor?

  • Ah, daylight saving and light thread trolling. Off to the 'get some fucking lights' thread now...

  • I didn't understand what you were commenting on, my moan about "fuck that's bright" or "dicks for thumbs". it was dicks for thumbs.

  • Lumicycle

    I run 2 front lamps in the winter, and tend to use both on the boost setting, each producing 1,650 lumens.

    One of the lamps is a mountain bike lamp, and I aim that a little in front as it has a wide beam.

    The other is a road lamp, and I aim that quite far in front and it has a narrow beam.

    In total: 3,300 lumens.

    It is daylight in front of me when I ride with that setup (most Winter riding). I have to be careful not to angle them too high as they can dazzle drivers. They dazzle cyclists anyway, so I avoid using dedicated cycle lanes with this setup, at least if they're on the other side of the road there's a chance they can still see.

  • I said literally melt people's faces off. soniamdisapoint.jpg

  • You could use one of these in conjunction with the Lumicycle?

    https://www.youtube.com/watch?v=W42SydwwrGc

    Although using it on its own gives a higher chance of them still having their eyes open when you melt their retinas.

  • You mean like the Blaze light? But hacked to remove the diffuser and angled at eye level?

  • Something to etch 'I drive like an arse' across the face of the most recent perp.

  • Ok, I mean you could always go for UV, for the insta-cancer effect, or Infrared to go for blood boiling. Basically take your pick from here: http://jetlasers.org/29-pl-e-pro

  • Nah, I've been doing night CX with 300 lumens. Quality>quantity.

  • go for UV, for the insta-cancer effect, or Infrared to go for blood boiling

    He wanted to melt the face, not zap the DNA or vaporise the blood. While it's surprisingly hard to find the latent heat of fusion for subcutaneous fat, it does seem that you don't need to raise the temperature very much to get it to melt, so latent heat is the key. We know that 1kW/m2 of white light is nowhere near enough, otherwise we'd melt in sunlight. The face is about 0.05m2, so we definitely need well over 50W to melt the whole thing, and the total power required will depend on the amount of time we are allowed to illuminate the target. There is a danger of simply ablating the surface without melting anything if we go for a very high power for a very short time, but if we try for melting with a low power/long duration pulse, people tend to run away before we can do any harm.

    We can burn people with thermal radiation dose of about 100 using this calculation method, which is equivalent to about 30kW/m2 sustained for 1s. Even with very good IR optics, we clearly need our emitter to be putting out >1kW to give ourselves a chance of doing some useful damage within the likely target illumination times, but we don't need to turn it on until we have the target in sight, so the battery need not be huge if we only want to zap a few people on each trip, the energy per shot is about 1kJ if we can generate a beam which doesn't fall outside the target area, compared with a total energy storage of about 30kJ for a typical smartphone battery.

    TL;DR
    You can't literally melt the face of somebody who isn't tied down

  • And then it gets a bit Bond Villain as you explain your evil plan.

  • Please have infinite #rep
    Things like these are why I love this forum.

  • Nah, I've been doing night CX with 300 lumens. Quality>quantity.

    ^This. I've been using some Philips light from Germany and while it's not insanely bright the optics and reflector is properly designed. Perfect vision on dark lanes. The best way I can describe it is that the light is relaxing and there's no hotspots. Unfortunately the light is heavy and the battery capacity could be better. Also the mount is a bit wobbly. Fine for a 2 hour dark spin though.

    http://www.philips.co.uk/c-p/BF48L20BBLX1/led-bike-lights-saferide

  • Well I've used decent 400 lumen lights.
    Works OK.
    But if buying specifically for night Road riding I'd go 600 minimum.
    Plus I dislike running my lights at max.

    I'd go for a internal rechargable battery 800 lumen jobbe, and run it on low when there's a bit of light around, and medium when stuff is unlit. Then press overdrive when needed.

    Something like this.
    http://www.moon-sport.com/product-detail.php?id=140

    Male sure you can scroll settings in a manner that doesn't drive you mental.

  • the optics and reflector is properly designed

    This should be the case for any StVZO approved light. Pity Philips gave up after getting the optics right and sent it out with a NiMH battery and wonky mechanics. I think the battery is a regulatory problem, StVZO have some weird rules about that.

  • It is some weird regulation. Really annoying. I bought the light for £30 so I'm very tempted to remove the batteries and hack in new ones. And a better mount. Unfortunately I don't know enough about electronics.
    Would a higher capacity but same voltage Li-ion battery pack work?

  • The 'no effort' way to get the advantages of lithium into your light (lighter weight being the main one, as self-discharge rate isn't really a problem for something you use daily), there are these. Without adding some kind of voltage conversion, it's hard to replace a quad pack of NiMh with LiPo since the cell voltage of LiPo is 3.7V, so one cell is probably too little to replace a 4.8V NiMh stack but two is way too much. If you were an experimentalist, it would be worth trying a single cell because the driver circuit in your light probably contains some kind of voltage conversion anyway, and it may have enough input tolerance to live with only 75% of the nominal design battery voltage. The other problem is that LiPo cells tend to be packaged in candy bar shapes, which don't lend themselves to integration into the space previously occupied by a quad of AA cells.

  • Hmm, will do some research. Found this in a quick google:

    http://singletrackworld.com/forum/topic/compulsive-bike-light-fettling-ultimate-road-set-up

    Actually reading through the specs, I think I have an older model with NiMH - the new Philips list 4x AA Li-ion as the power source. hmmm.

  • exposure strada...i picked one up second hand for around £100, they are just the best. I ride unlit dorset roads as my commute, the light is just brilliant. i would definitely get another one even at full price, they are really worth it.

  • I agree with JonD. The battery life is good too.

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Lights

Posted by Avatar for Skülly @Skülly

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