I need to run three LEDs for indoor indication purposes and want them to be around 500 - 1000 MCD. I will run them off batteries and I'm wondering if there is anything I can do to increase battery Life since I don't want them to be that Bright anyway.
They will be wired in parallel and need to be constantly lit when powered on. Series Circuit is not an option because I can't fit a higher voltage battery. 3-4AAA is the most I can fit inside. I also want to keep the Circuit as simple as possible.
I have some options for leds that are rated at Everything from 1000 - 15000 MCD. They are all rated at around 2-3.6V and 20mA.
Is it better to choose a brighter LED and run them at maybe 1-5mA or so to get the wanted brightness by adding bigger resistors or should I use a more appropriate LED for the wanted brightness with smaller resistors? They are all rated at 20mA.
I know that resistors waste energy but I'm not concerned with that as long as the energy wasted by the resistors is smaller than the energy saved by running the LEDs at lower currents. Unless it will get really hot because it's inside a box.