At a price of US$700/ton, the rejected shipment was worth US$280,000!!
What's The Cost of Proper Optical Calibration?
Technidyne acquired the rights to produce the 'GE' directional brightness tester with the understanding that calibration is very important. Monthly calibration standards from Technidyne cost about 0.1% of what a rejected shipment (above) might cost. As the 'yellow book', Technidyne's Seminar Manual - Measurement and Control of the Optical Properties of Paper, states, "an instrument can only be as accurate as the standard to which it is calibrated."
Proper optical calibration...
- insures the instrument is working correctly
- provides diagnostic information
- addresses photometry (linearity & amplitude calibration)
- addresses spectral (wavelength calibration)
- is specific to the geometry
- provides a means to compare data from measurement to measurement (repeatability), instrument to instrument (reproducibility) and location to location
- must be done on a regular basis
- is performed by trained personnel