Richard,
Just wanted to let you know how pleased our company is with the Rudolph J57HA Automatic Refractometers. We currently have two of the instruments in service in our sugar testing laboratories, and are in the process of ordering three additional refractometers. Before the decision was made to switch our laboratories to the J57HA Refractometers, rigorous testing was done on the instrument over the past year in our Quality/Research Laboratory. It has been our policy when doing research type work, using our old refractometers, that we place a sample on the prism, set a timer for two minutes, then press the “Read” button until we get three readings in a row that are identical (this could take up to 12 readings). With the J57HA instrument, we place the sample on the prism, press the “Measure” button and in about 15 seconds we have a stable number. The instrument is so stable in fact, that I can honestly say after using the instrument for over a year, we have had a different reading from the original measurement, no matter how many times we repeatedly press the “Measure” button. This instrument has greatly reduced our sample time and improved our accuracy. Calibration of the instrument is easy and rarely required. We have had no problems or issues with the two instruments that we currently have in service. I would highly· recommend the Rudolph J57HA Refractometer over any other brand of refractometer that I have used or tested throughout my many years working in the sugar industry.
Reguards
Richard Reisig