Why are my LEDs so dim?

I’m not sure what’s gone wrong here. I’m using these 3mm red LEDs with a couple different 1/8 watt resistors, from 330 ohms down to 150, and it still seems really dim at 150. I haven’t seated the LED in a button yet, so it might look brighter, but it really doesn’t seem nearly bright enough. What could the problem be? I’m using the VCC on a Madcatz retro stick PCB as a power source, and it looks like it’s soldered properly.

So far, I’ve finished all the busy work on this stick while pondering this problem, and I’m not sure what else to do. I’ll post pics once the stick is finished, but it’s looking really nice so far. Fully functional now…just need those LEDs working. Using this image as art–looks classy with Seimitsu clear buttons and cutout art.

Thanks for any help!

edit: Is it just a dim LED? I just swapped it for a green one which looks nice and bright.

Perhaps your resistors aren’t needed? You have to look at the amperage/voltage rating of the LEDs to know what resistance to add I gather, and also there is a luminace rating on LEDs. I’m not too well versed on this stuff, but here is a link that may help.


Look at the “MCD” rating on the page, it has typical MCD listed as 5.
5 is extremely low… those LEDs wouldnt shine light over a distance of more than an inch, and you have resistors on them lowering their power even further.

On our website we sell 14000 MCD LEDs, to give you an idea of what brightness is ideal for this kind of work.