I thought I had this figured out but my last couple of batches are falling way short from my stated SG. My last two batches were identically 0.6 too low in gravity as read with the refractometer. For example, I read 12.6 Brix (approx 1.052) with my refractometer but the hydrometer reads 1.049 (approx 12Brix). My starter read 1.032 (approx 8 Brix) with the hydrometer but reads 8.6 Brix (approx 1.035) with the refractometer. Can't I just 're-calibrate' my refractometer by dialing in an 8 Brix reading when I read my starter which was at 8.6 Brix?? please help, and thanks, cheers!!