Figure 1. Site 1019 L* record comparing results of standard RGB to L*a*b* conversion (A) with those of the four-color conversion developed in this study (B). Black line = Hole 1019C, gray line = Hole 1019E. The standard conversion cannot compensate for a recalibration of the video camera during the scanning of Hole 1019C. The nearly identical values produced by the four-color approach show that camera effects are successfully filtered out. For further discussion, see text.

Figure 1. Site 1019 L* record comparing results of standard RGB to L*a*b* conversion (A) with those of the four-color conversion developed in this study (B). Black line = Hole 1019C, gray line = Hole 1019E. The standard conversion cannot compensate for a recalibration of the video camera during the scanning of Hole 1019C. The nearly identical values produced by the four-color approach show that camera effects are successfully filtered out. For further discussion, see text.