I was told on the Shapeoko forum that my 10bit MA3 analog shaft encoder method was so Rube Goldbergish by a moderator there compared to using an electronics means to control the lasers intensity. By us using a timing belt configuration & ratio change from the stepper to the encoder, we are able to keep the steps per low enough and still have the 10bit resolution with the 0-5v analog out to the Flexmod P3 laser driver.
We tested a 10bit DAC from J-Tech Photonics with Mach3 and it required 40000 steps per inch and it would lose position/steps because of the very high and fast stepping it had to process even when setting Mach3 to a high Kernel Speed. The 10bit MA3 shaft encoder works very good with Mach3 too. US Digital does offer a 10bit & 12bit PWM version also.http://www.usdigital.com/products/encod ... /shaft/ma3