from Matt Perger's experiment: in ascending order of hole size hario paper filter: 20 nom. (30~40 meas) um Ameuus o2 50k holes: 30 um Ameuus o1 10k holes: 100 um Able disk fine: 150 um? Able disk standard: 300 um? metal filter for handdrip: 800目, 22um CONFIL有田燒陶瓷濾杯( made of alumina powder): 50 um feebie 細粉篩粉器: 80 目, mesh 80, 180 um VST espresso filter basket: 170um unknown brand made in italy, double portafilter basket: 300um, 715 holes mesh size table ( ASTM ): Question: sifting claims to reduce bitterness in cup ( i dont think it's a bad thing), and brings clarity. Most says they also let more coffee oil into cup ( wrt paper filter) OTOH, some minor nuances might also be filtered out too, and cause less complexity/ monotonic question: will too small hole size also blocks coffee oils? coffeeastra