I'm working on a dimmer and wondered like you have about
practical dimming increments. What I thought you could do is
use a display in conjuction with the dimming phase-changing
process so as to compare the phase angle with the brightness
of the bulb. I suspect this may be necessary when using a
variety of bulbs - you might not be able to guarantee that a
table designed for one type of bulb is applicable to another

Just a thought, no practical experience to back it up with

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