StanJohnson
Well-Known Member
I've checked this, both read 1.000 with pure water at 60F. I'm more inclined to trust the hydrometer than the Chinese refractometer. I suppose a more scientific calibration test could be done... both could be off for all I know.
The instructions that came with my refractometer say to calibrate it at 68*F. It also states, "When working temperature of the room or environment (not the sample) changes by more that 5*F, we recommend recalibration to maintain accuracy." Now that it's summer in Florida, I won't see 68 in the house or outside for months. What I do is take my refractometer and distilled water outside with me when I brew. I then recalibrate throughout the brew day, since it may be in the low 80's when I start but will be in the 90's when I finish. I did this last time as well as take hydrometer readings. My readings were within a few points of each other. I did the same thing just before I bottled last time. Using a alcohol correction calculator with the refractometer, both reading were the same, which makes me confidence in my refractometer readings and my recalibration process. YMMV