Optica 2WAJ Manual De Instrucciones página 11

7.0 NOTE ABOUT THE MEAN DISPERSION VALUE
Table 1: Dispersion Table for Abbe Refractometer Formula for calculation of the mean disper
sion value: nF-nC = A + B*0
The reading of the 0's for the corresponding Z of all compensators takes positive sign
(+) when Z<30, and takes negative sign (-) when Z>30.
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