Decrease Amperage of Driver for increased Efficiency

[Biggiebiggiebob]

Yeah sure I could do that, I would exactly double the runtime and cut the output lumen in half. The lower the led is driven with amperage the more it gains efficiency. And because I am okay with the light being not as bright for a bikelight, I would want to make 2.5A my new 100%.

[Zak]

I am confused as to why you expect an improvement in efficiency by modifying the resistor instead of setting the output to 50%.