Choosing correct LED mcd for outdoor indication

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peterlonz
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I don't wish to ask dumb questions about basic LED applications but ...
Yesterday I bought a 12 mcd, 5mm Dia, red LED, through hole mount.
It was to replace an unexpected failure of the previous unit: supposed to suit 12VDC supply & containing a built in resistor.
The application is a 12VDC regulated, 2 amp capable, PSU.
The original LED was nice & bright & easily seen outdoors.
This was good because the 240VAC power on/off rocker switch containing a red neon is not sufficiently bright
My replacement LED is relatively dim & I need to cup my hand over it (when outdoors) to be sure its on.
Now by chance I made a silly mistake & used a 100 ohm resistor instead of the 300 Ohm which is what I calculated should be used.
So I am expecting the LED to fail soon, but it should be much brighter surely with the higher current.
I can't figure out this dilemna.
I suspect 12 mcd (@ $0.25 ) is probably a poor choice but there seems very little choice between this low output & the much higher rated 5000 mcd & above.
Suggestions please?
 

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Yes, that is a very low powered LED. 1 Candela is roughly the brightness of one candle.

So 12 mcd is about 1% of 1 Candela. Not much.
5000 mcd is 5 candles, so, much better.

You can get a brighter LED and just run less current through it. They are usually highly efficient, so try calculating the resistor with 20 mA flowing in it. Maybe 470 ohms.
 
I'm thinking you're shopping at the wrong place. You can get pretty much any LED you can imagine! I like shopping at Digikey (http://www.digikey.com) for parts.

5000mcd isn't really that much. Remember, a candle is 1000mcd.

Here's what I'd go with: http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=C4SMF-RJS-CT0W0BB2CT-ND

Rating is 2640mcd price $0.20

From the Datasheet.
This oval LED is specifically designed for variable-message signs and passengerinformation
signs. The oval-shaped radiation pattern and high luminous intensity
ensure that these devices are excellent for wide-field-of-view outdoor applications
where a wide viewing angle and readability in sunlight are essential.
These lamps are made with an advanced optical-grade epoxy that offers superior
high-temperature and high-moisture-resistance performance in outdoor signal
and sign applications. The encapsulation resin contains anti-UV material in order
to reduce the effects of long-term exposure to direct sunlight.