Even instruments of the same brand and geometry may not give exactly the same absolute readings of a product. If difference measurements only are made (measuring the difference between a product standard and samples), the absolute values of the different instruments are irrelevant. However, if it is important that measured absolute values be very close together, you may hitch the instruments together. The process involves assigning one instrument to be the reference, or master, unit and mathematically adjusting the secondary or slave unit(s) to read the "same" values. Note that the best hitch results are obtained when the instrument set contains units of similar geometry. Hitched instruments should all have either diffuse illumination and 8° viewing or 45° illumination and 0° viewing. The two geometries should not be combined in a hitch.
Click here for more information on the hitching process.
For directions on how to actually implement the hitch using your instrument, locate "hitch," "hitch standard," or "transfer standard" in the index of your User's Manual.
If additional assistance is required, you may contact HunterLab.