Coffee preparation techniques besides espresso like pourover.
by jpender » 32 minutes ago
I only have the 0~40% Brix reader at hand, and I have no problem reading it at 0.1% by eye. (even my eyes are pretty bad now) The 10% Brix reader will be even easier to read. Using a light moving around the flat top side to change the illumination angle will help to identify a very sharp edge, which is the boundary formed by the critical angle.
I have no need to use machine vision yet, but if there is enough interest I’ll try my Raspberry Pi camera to make a demo. I’ll also try to run some Zemax simulation that may come out some low-cost lens solution to replace the existing one. As I said, it is fun toy to play with.
For espresso an inexpensive handheld optical refractometer makes a little more sense since the concentration is on the order of ten times greater. A precision of 0.1°Bx isn’t bad at all, never mind half that if possible. I wasn’t interested in one of these things when I was making brewed coffee. But now that I have an espresso machine I may buy one of these and see how well it actually works. They sell a 0-18°Bx version with 0.1° rulings. For $30 it’s worth a try.
by jmotzi » 18 minutes ago