I conducted a test of some LEDs that I purchased from various sources and some hacked out of X-mas light strings. Photographed with digital SLR camera on manual exposure for consistency and white balance set to daylight. I shot through a white piece of plexi. First shot was with the plexi right up against the LED dome and second of the series was with the plexi raised a couple inches to show beam spread.
ROW A
1. ebay seller "Asia Engineer" (not user name but has that posted on his pictures). LED looks bluish, but is an odd green bluish by the eye. Dimmest of all to me.
2. SuperBrightLEDs.com 1,800mcd 15 Deg white. Least bluish and brightest. Most expensive, but best I have.
3. Generic brand chrismas light (flange less 5mm) bluish white good brightness. Purchased string at Home Depot (HD)
4. From ebay seller cece718 (ships from US). Less bluish, but a tinge of violet to the eye. Better to me if you don't like the bluish ones.
ROW B is the beam spread shot of these.
ROW C
1. 3mm hacked from Sylvania 50 LED globe light string sold at HD. A little blueish but Brighter than even the Superbrightleds 5mm white! Too bad it is wide angle. Not best for flashlights.
2. Superbrightleds 3mm white. Not nearly as bright as 1.
3. Superbrightleds 5mm warm white. bright and moderate wide angle.
4. 5mm warm white from light string purchased from Menards. Tighter beam. Good brightness and tighter beam. Only 17 cents each. A few have a resistor soldered to them.
ROW E shows the interesting Radio Shack LED (in position #2) compared to the typical cool white LED. It is around 4,100K color temp. Brightness is good, but darn it, it is too wide angle for flashlight and too expensive $2 for two pack.
That's it for now. I'd like to set up an accelerated fade test by driving these at 40ma for a few days to see how
they hold up.
