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    LED light as a "beacon"

    What do you mean by "traditional LED"? Red and green LEDs both predate white LEDs (by a couple decades), and while the radiometric efficiency of white LEDs is greater than green LEDs, it's on par with red. But radiometric efficiency aside, a direct emission red or green LED will almost always...
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    LED light as a "beacon"

    I'd be looking at boating lights for this - white beacons rated at 2 nautical miles with 360 degree visibility are readily available, with red and green options also available if you dig a bit (or are willing to put together something made up of multiple directional sources). Power requirements...
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    Anti collision strobe

    Without knowing the design of the driver, it's impossible to say what would be involved in changing the output characteristics. OTOH, overdriving a unit that's likely already running at the limits of the parts (it takes a LOT of lumens to make a visually bright flash, due to the short duration)...
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    {{ Stuff that just works }}

    Removing the guard from an angle grinder (even without a saw blade in it) is also a poor choice, unless you happen to like shards of abrasive wheel embedded in your body.
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    Powering/Driving a Stadium type of light

    Before diving further into fixture design, you need to figure out exactly what sort of light levels you need, along with what sort of beam pattern based on your expected fixture locations and what sort of size you're willing to deal with. For recreational sports fields, a light level of...
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    Powering/Driving a Stadium type of light

    Thermal imaging of illuminated LEDs is very difficult to get accurate, due to the visible light emission from the LEDs, and the different emissivities of the various parts in the image. So, although the thermal imaging can be useful for finding hot spots and places to put thermocouples, you'll...
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    Powering/Driving a Stadium type of light

    You do not want to treat LEDs as a constant-voltage load, which is what that linear regulator based approach is doing (assuming a typical 3-terminal linear regulator or LDO). The voltage varies with the LED bin, temperature, drive current, and possibly also LED age. A current-limiting resistor...
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    Bringing a 6P in to the 21st Century

    It is worth noting that if you don't need the 5700K, the neutral and warm Malkoff drop-ins use high-CRI emitters.
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    Things I've learned the hard way . . .(Part 2)

    You are not alone in this - the Haribo Sugar Free Gummy Bears are an infamous example
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    Powering/Driving a Stadium type of light

    Start by figuring out what sort of performance you actually need - if you actually need a beam angle under 20 degrees, you're probably looking at high power LED packages, or big reflectors for CoB packages (looks like a 6" reflector will get you a beam angle in the 10-15 degree range woth an...
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    Battery life for low power draw devices

    Energizer provides discharge curves for both their alkaline and lithium batteries at An L91 (Lithium AA) is good for ~3500mAh at discharge rates under 100mA, with a reasonably consistent output voltage over lifetime. The E91 (Alkaline AA) is good for perhaps 2700mAh...
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    DIY Hunting LED Spotlight - design suggestions

    Comparison was to the 70W HID, on the assumption that if the OP was looking for more output, they'd go for the more powerful upgrade. So 3x XP-L HI to match the 50W seems about right
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    Looking for something specific.

    Pelican 2460 and 5050R are both close but miss on a few points.
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    noteworthy timeline of lights

    There's a few things at play with rated lifetime decreasing. The first is that, indeed, LEDs cost money so using fewer and driving them harder results in a lower cost product. But the other big factor at play here is that the early lifetime numbers were based on some pretty wild extrapolations...
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    Replacement bulb for microscope lamp

    Running an 8V lamp at 6V results in a lower output from the lamp, but a rather longer lifetime. At 6V, that lamp was likely drawing about 9W. A #81 lamp is a clear bulb and slightly lower output than stock, but is pretty close and is plenty cheap enough to try as an experiment, especially if...
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    Disaster Light for Emergency workers

    Instead of asking your team to use different gear in a disaster situation than what they use day-to-day, why not have the "extended operations" kit be spares for the primary lights your team already uses? If your existing lights can take AA NiMH cells and you have access to power, the spares...
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    best throw head for malkoff md3

    Double the candela results in an increase of the throw distance (distance to a specific light level) of about 40% due to the inverse-square law. So not a massive increase, but not zero, either.
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    Flashlight Grip Tape

    Check your local sporting goods store for hockey stick tape
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    Novatac 120T serial 12269 pics and questions

    Got a link to those old posts? I'm happy to be educated, but I didn't find any posts on this topic with a couple searches and looking through about 20 pages of search results. And it seems like you were being sarcastic, but it is possible to correlate measurements made with a light meter in an...
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    Novatac 120T serial 12269 pics and questions

    Using a light meter (lux or footcandles) to measure lumens is challenging because you need enough measurements to be able to take the beam distribution into account. But assuming that you can take the required number of measurements (e.g. by using a goniophotometer), color and tint have almost...

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