Exploratory work by AMS, reported at BW 2004, showed considerable promise for relating digital, monochrome camera, image-based measurements to Human Classer Leaf Grades. More specifically, the measurements were of particle count C in and percentage area %A occupied by trash particles in the HVI 9 in^2 object field.

Building on that exploratory work, STI reported digital, color scanner, image-based C & %A results for a 28 in^2 in object field in BW 2005. These results showed promise for charts having so-called circular boundaries in C & %A in determining LGcc. The STI method also has potential for extensions to bark, grass and preparation.

During 2005, the LGcc method has been refined and the field experience base has solidified. Selected data will be shown. STI is now using its circular chart determinations of Human Classer Leaf Grade in all gin-based IsoTesters instead of the neural network method, which it pioneered.

This paper is an up-date on LGcc, with focus on the interpretations of C & %A vs Human Classer LG correlations. Its conclusion will include comments on the technical and market consequences of moving to instrument leaf grade.