Product Review: Duplex II and Rayner Dialdex Refractometers
For decades, I used a Gem Instruments Duplex II refractometer exclusively. Many regard it as the best refractometer available in the United States. In Europe, on the other hand, the Rayner Dialdex refractometer is considered the best. Shipping costs have kept these from being regularly traded across the Atlantic. As a result, most people don’t have a choice of brands. However, you can safely say both are top-quality manufacturers.
While reviewing “no name” refractometers, I read that the Duplex II is the only refractometer designed specifically for spot readings. As I discovered, the “no name” brand units were almost useless at spot readings. I was left wondering how much their smaller size had to do with that.
As an experiment, I purchased a Rayner Dialdex. It’s considerably smaller than the Duplex II and about the same size as a “no name” brand. …