refractometer / hydrometer

[Lauritsen]

My ATC refractometer shows 10.8 but my hydrometer shows 1.046

Why this discrepancy?
which one to trust?

 

[sniktaw]

Do you mean why is one 10.8 and the other 1.046? 10.8 is the brix and 1.046 is the specific gravity. Two different ways of measuring the sugars, kinda like Celsius and Fahrenheit. The refractometer usually has two scales on it, one measuring s.g. and the other measuring brix.

 

[microbusbrewery]

Depending on which converter you're using, 10.8°P should calculate out to a specific gravity of 1.042 or 1.043. Is that what you're asking...1.043 versus 1.046? Assuming so, one or both may need to be calibrated.

 

[dmtaylor]

The conversion factor is about 4 (and then stick 1.0 on the front). So 10.8 brix is the same as about 1.043, which is reasonably consistent with 1.046 from the hydrometer. You can be assured that the gravity is someplace in that range 1.043-1.046. Both instruments are prone to errors and are plus minus about 0.003. So this all makes sense. Which one to believe? They're both right, plus or minus 0.003.