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Where to buy LED flashlights in New York City?

Discussion in 'General Electronics' started by wylbur37, Apr 9, 2004.

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  1. Checking "invisible" stamps (cover charge paid or over/under 21) at
    night clubs for example. Also useful for illuminating the strip in
    American paper money. No lap-dancing stripper should be without one.
    ;-)
     
  2. Dave VanHorn

    Dave VanHorn Guest

  3. Ken Weitzel

    Ken Weitzel Guest

    Hi...

    Those new scanners (I don't have one yet) have 3 seperate
    light sources.... one R, one G, and one B, so that the
    light source can be made any temp you might want.

    In the case of the cameras, the entry level ones just
    default to a bright sunny day and leave it up to you
    to compensate with post processing.

    The mid levels have a few pre-determined choices,
    like sunny, cloudy, incandescent, flourescent, etc
    from which you may choose.

    The top of the line cameras allow you to use
    an 18% gray card to set with.

    Take care.

    Ken
     
  4. jakdedert

    jakdedert Guest

    in message
    It's the 'main' advantage, yes; but not the only one by any means. Drop
    your maglite when it's turned on and see what happens...or take two
    maglites, turn one on for an hour or so. Then replace the cells and compare
    the light output with a brand-new maglite. The bulbs silver up pretty
    quickly, diminishing the output appreciably.

    The only way to get full output from a mini mag is to have new cells, a
    brand new bulb, and a well-polished reflector (and be careful not to drop
    it)...none of which are requirements for a decent LED flashlight.

    jak
     
  5. Guest


    Speaking of strippers... Forensics people use UV lights to look for
    'male bodily fluids'. Cat urine also shows up under UV.

    I have seen pens on eBay whose ink only shows up under UV. Suggested
    uses were marking items sent in for repair to ensure you got the same
    unit back. Marking properly so it could later be identified (thief
    wouldn't see markings). Lots of other uses I can think of, too.


    -Chris
     
  6. Jeff Wiseman

    Jeff Wiseman Guest

    Comments below:


    Well the EverLED also has regulation built in as well. On the
    larger D cell maglites It can go for well over 20 hours before
    starting to really dim. This is because it's using more of the
    battery. A regular bulb will show much more dimming prior to that
    even with more life left in the batteries. "dead" batteries with
    a regular bulb can be put into a light with the everled and they
    can then still produce significant light.

    You're right though, it's a bit more than just the LED. The
    EverLED only needs 1.5volts (a single cell) to light but can be
    used in a 6 cell (9 volt) flashlight. Try putting a 6 cell bulb
    into a 1 cell flashlight and with a fresh battery it still will
    not be real usable.

    BTW, I was also not sure if it was a Luxeon Star or one of
    LumiLED's other products being used in the EverLED.


    Yes, this is true, but using the CR-123 with LED technology can
    help some. Also, Lithiums do NOT have the problem of alkalines or
    any rechargables when used in freezing temperatures.

    Even with rechargable batteries though, you'll need to change
    them 4-7 times where some LEDs will only need it once. Also, with
    the small CR-123 type lights and their high intensity outputs
    aren't always useful. You can have too much light. That's why
    things like the ARC4+ are intrguing since they can be turned way
    down if desired. Although you only get about 30 minutes at top
    intensity, it can be extended to over 20 hours on the lower settings.


    I do stand corrected. You are absolutely right in that a fresh AA
    minimag with a new unsilvered bulb IS brighter than the ARC AAA
    at first. But if you turn them both on and leave them on for,
    say, 3 hours or more it won't be. The usable light from the
    minimag is gone and you'll have a few more hours of usable light
    from the ARC. If you leave the minimag on when it's batteries are
    run down, this is one of the things that accelerates the
    silvering of the bulb so if you leave both on for, say 10 hours
    continues, the ARC will need a single new AAA battery whereas the
    mag will need two new AA's and a new bulb if it's to work as well
    as it did 10 hours earlier.

    However, the light from the ARC is whiter and more even than the
    minimag at any setting. In general, I PERSONALLY have found that
    the overall performance of the ARC over the minimag has resulted
    in my minimag being left unused a lot of the time. YMMV

    I shouldn't have misrepresented the total output of the AA
    minimag that way though. Thanks for correcting me.


    Yes, in part. Also though is the fact that as the batteries wear
    out and their Voltage drops, the usable light from the
    incandescent drops much faster. For example, I had a nearly
    "dead" battery in a Maglite Solitare (the single AAA version).
    The mag would only barely glow. I take that battery and put it
    into my ARC AAA and it lites up as bright as with a new battery.
    I was able to get another couple hours of light out of the
    maglite's "dead" battery. And the output of the Solitare when
    fresh with new batterys and bulb is about the same as the ARC
    (although I prefer the evenness and color of the ARC for reading).

    LEDs can not only draw a battery down slower for a given light
    output, that can be made to draw them down FURTHER using up more
    of the battery before it needs to be disposed of.


    I have a 3Dmaglite with an EverLED, a minmag, a mag solitare, and
    an ARC AAA as well as a handlful of other incandescents. I've
    experimented a lot and have done my share of research on these.
    With the exception of the output mistake that I made and that you
    corrected for me, I wouldn't really call it hearsay. However,
    there certainly is a lot of it out there.

    Again, although I'm not an active member of the forums, I would
    encourage anyone interested in these topics to explore the URL:

    http://www.candlepowerforums.com

    There are some guys there that are very much into the hobby who
    are using some very decent methods of doing comparisons on issues
    such as these. Check out the reviews forum at:

    http://www.candlepowerforums.com/ubbthreads/postlist.php?Cat=&Board=UBB16

    There are some interesting collectings of output vs throw and
    runtime plots for many different flashlights.

    - Jeff
     
  7. Jeff Wiseman

    Jeff Wiseman Guest


    Check out Surefire's website (www.surefire.com). You can get them
    there by the box for as low as $1.25 each.

    - Jeff
     
  8. I can say for Philadelphia, especially its suburbs:

    Target sells a few LED models by Dorcy.

    Sears and a few hardware stores have a Dorcy LED model or two.

    The availability gets much better with mail-order and web retailers such
    as Brookstone.

    I have seen a couple LED "keychain lights" at K-Mart and Rite Aid.

    Please check out a major LED, LED product, and LED flashlight review
    site - http://ledmuseum.home.att.net/ledleft.htm

    This site mentions dozens of LED flashlights and where to get most of
    them - mostly other than stores that you can walk into.

    - Don Klipstein (, http://www.misty.com/~don/ledx.html)
     
  9. Ones as bright as conventional ones can be made and are available, but
    they cost more.

    I have a darker suspicion: Many retail-available flashlight brands
    (Mag is a notable exception) are brands of battery manufacturers. Many
    retailers sell batteries. And when batteries weaken, an incandescent bulb
    greatly loses efficiency while LEDs tend to have much lesser to sometimes
    no loss of efficiency from being underpowered. LEDs will give you enough
    light to see by from batteries too weak to make an incandescent flashlight
    bulb outshine a cigarette. Also, when batteries get weak incandescent
    bulbs have less resistance (continue to drain the batteries heavily)
    while LEDs have increased resistance (effectively go into "energy
    conservation mode"). And the manufacturers and retailers that are
    reluctant to sell LED flashlights make a lot more money from selling
    batteries than from selling flashlights.
    Note that the somewhat common Eveready LED light takes batteries of a
    size that I don't see their conventional flashlights using.

    - Don Klipstein (, http://www.misty.com/~don/ledx.html)
     
  10. I think that was optimistic. LEDs have only advanced about half as fast
    as computers have throughout the past few decades. I expect that a decade
    from now, fluorescents will be more economical than LEDs for general room
    lighting.
    It is easier for colored LEDs to outperform colored lights with
    incandescent lamps than to have white LEDs outperform uncolored
    incandescent lamps. LEDs are normally good at being specialists at
    producing light of one particular color or another, while making colored
    light from an incandescent requires having a filter that blocks some of
    the light.

    - Don Klipstein (, http://www.misty.com/~don/ledx.html)
     
  11. BEWARE - they probably do not produce the required amount of light, and
    especially probably do not produce the required amount of light into every
    direction/angle at which a legal requirement is specified.

    Even at auto parts stores such as Pep Boys, I see on display for sale
    bulbs that are obviously illegal. The more honest of the illegal
    fashionable bulbs/lamps/lights have disclaimers along the lines of:

    * "Check local laws before using" (usually means unlawful for use on all
    public roads under any municipal and/or county and/or state
    jurisdiction of most to all of the 50 US "states").

    * "For off-road use only" (illegal to use or maybe even have operational
    on your vehicle while your vehicle is on a public road anywhere or at
    least in most locations of the USA)

    In my state, "off-road" lights on street-legal vehicles must be either
    (maybe both) be covered or otherwise rendered unusable in a way that
    requires someone to be outside the vehicle to restore usability, in
    addition to requiring being disconnected and not just by a switch within
    reach of a seated vehicle occupant (I heard that plugs and jacks are OK,
    possibly even if in the reach of a driver in the driver's seat, but this
    is hearsay).

    * "Racing" - as in legal on a race track but not on a public road. Ever
    notice that real race cars lack "racing lights"?

    As for safety - in my experience, most cars have redundant bulbs for
    brake and backup and tail lights and rear turn signal lights.
    The "Driver Manual" for my state recommends frequent checking that one's
    car has all bulbs working and to immediately replace any that are not
    working. I have heard that in my state and in a neighboring one, a burnt
    out bulb having a legally required function can get you a ticket that can
    be negated by having the bulb replaced by a professional mechanic
    giving you a receipt within 24 hours after the time on the ticket.

    - Don Klipstein ()
     
  12. The usual white LEDs have CRI anywhere from 75 to 85, much better than
    the much-maligned and traditional, stil somewhat popular "Cool White"
    fluorescents that typically rate a 62.

    Also note that digital cameras largely avoid a problem that most films
    have with most non-daylight non-incandescent non-xenon white light: Many
    white light sources (other than incandescent and xenon) are to some extent
    or another optimized for human eyeballs, which do not see the various
    wavelengths of red visible light as equally as most films do. So a lot of
    white artifical light sources look less red to film than to human vision.

    - Don Klipstein (, http://www.misty.com/~don/dschtech.html)
     
  13. Cold cathode fluorescent is actually a longlife technology. Also there
    is no significant life expectancy penalty for frequent starts. These
    things outlast hot cathode fluorescents!
    The compromise of cold cathode fluorescents is that they are a little
    less efficient than hot cathode fluorescents, along with some efficiency
    compromise from having their diameter usually smaller than optimum for
    maximum efficiency from fluorescents.

    NOTE - smaller diameter raises the voltage drop, which mitigates the
    efficiency-reducing factors of short lamp length and/or high "cathode
    fall" (as in "cold cathode").

    - Don Klipstein ()
     
  14. Jeff Wiseman wrote:

    [snip]
    Again, I don't believe you one bit. Ya know, if you continue to distort
    the truth, your believability will be seriously compromised. Like my
    mother used to say, "I told you a million times not to exaggerate!"

    But the LED does not put out the same amount of light at lower battery
    voltages, as you seem to imply. This is a given, and of course there is
    a point where the LED's output is no longer adequate. Just for grins,
    I've put old batteries into both my ARC AAA and into my Dorcy single AAA
    cell flashlight, and let them run down the battery. When the voltage is
    so low, the light output is seriously reduced. Try it yourself.

    I built a few of the circuits shown here
    http://elm-chan.org/works/led1/report_e.html
    except I didn't use the D1 diode or C1, I used the LED itself as the
    diode. It's a very simple circuit. These depend a lot on the
    transistor's gain and low Vce(sat). I've had one that barely worked at
    ..55V, but that's not realistic because the light is barely visible. At
    ..8V it puts out somewhat more light but nowhere near what it puts out
    with a fresh cell. So I can "run down" a supposedly dead AA or AAA cell
    with this circuit, but the light output is much less than adequate at
    low voltages.

    As for CPF, I find that most of what they are doing involves using the
    Maxim or LT chips, and they seem to be stuck on using the CR-123 lithium
    cells. Well, that's not the most economical, and I'm one who, like you,
    would rather run down some AA cells. They're on sale for 25 cents or
    less (alkalines), and you can't beat them for economy. See
    www.cheapbatteries.com for some real cheap batteries.
     
  15. Same for www.cheapbatteries.com. But you can get AA alkaline cells for
    a lot cheaper, a whole lot cheaper.
     
  16. [snip]
    I think I like my Opalec Newbeam better. I bought a pair of Opalec
    Newbeams last year and I've been using them regularly since. They have
    three LEDs instead of just one, but are more expensive ($27). These
    only fit later models of the Mini Maglite - check out their website.

    http://www.opalec.com/products.html
    New lower price, see http://www.pocketlights.com/opalec.asp
     
  17. What puzzles me is that far fewer auto makers have replaced
    incandescents than have truck and bus makers. It seems as tho almost
    all buses and trucks have LEDs in their taillights, but few later model
    autos do. I know the new Toyota Prius has some LEDs, but not all, in
    the taillights.

    Maybe trucks and autos use them because of the reliability and low
    maintenance. Auto makers probably don't because they're not as cheap as
    incandescents.
     
  18. Most people don't shop on Ebay, they buy their batteries at the grocery
    store or worse yet, Radio Scrap. And they're _not_ cheap there!
     
  19. I can buy a brick of AA alkalines for $.25 - $.30 each not on sale, and
    even less when they're on sale. Hard to beat that for inexpensive
    batteries, and everything seems to use AA cells.

    What's bothering me is that very few flashlight makers have progressed
    to designing their lights to use rechargeable cells. If more AA cell
    sized flashlights would be designed to use Ni-MH cells, the world would
    have a lot less batteries to trash, recycle, etc.
     
  20. Dave VanHorn

    Dave VanHorn Guest

    Half the people you meet are below average intelligence. :)
     
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