When shopping for a refractometer, one of the features you should be looking for is Automatic Temperature Compensation or ATC. This is a particularly important feature especially when working in the field where you are being exposed to the elements.
Refractometers can be dramatically effected by temperature. This is because as objects get colder they shrink and as they get warmer they expand. In the case of refractometers, the glass prism that light goes through is expanding and contracting with temperature. This alters the level of refraction that is given to light as it passes through the prism.
If you’re in a situation where the temperature is always changing it can be a challenge to get an accurate reading. But when a refractometer has ATC then temperature variations are taken out of the picture. (For more about how refractometers works see: How Refractometers Work)
ATC automatically compensates for any change in refraction that temperature may have on the refractometers prism. It does this by slightly changing the angle of an inner lens as the temperature fluctuates.
A long piece of metal is attached to the lens and runs down the barrel of the refractometer. As the temperature changes so does the length of the metal strip through expansion and contraction. This alters the angle of the prism just enough to correct any errors that temperature may be causing.
All the refractometers we offer have ATC which incorporates this method of correction. For more information about our refractometers, please visit our website.
Ed Kraus is a 3rd generation home brewer/winemaker and has been an owner of E. C. Kraus since 1999. He has been helping individuals make better wine and beer for over 25 years.