what is the most efficient way to add a dimmer to LS ZTX circuit?

[ake]

what is the most efficient way to add a dimmer to LS ZTX circuit?

I know the easiest way is to add a potentiometer at the output, but that just wastes the power and it doesn't save the battery.
I am thinking about adding a switch or potentiometer at the Rsense so I can vary the output current. I plan to do a mod on my headlamp, probably a PT Solo.
The reason behind this is that there are times I don't need the whole brightness of the LS and there are times that a runtime is a more important than the brightness.
Has anyone done this before? How feasible is this idea?

Thanks for any input,

Ake

 

[The_LED_Museum]

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