Table 1.

Mean optical attenuation coefficients per probe with range (visual representation in Figs. 1 and 2). Note that per probe the smallest and largest ranges in ${\mu }_{\mathrm{oct}}$ are 0.06 and $0.33{\mathrm{mm}}^{-1}$, respectively. Between probes, the smallest and largest differences in measured ${\mu }_{\mathrm{oct}}$ are 0.15 and $0.65{\mathrm{mm}}^{-1}$, respectively.

Volume Concentration (%)	Measured mean (range) attenuation in ${\mathrm{mm}}^{-1}$				Mean attenuation $+/-$ standard deviation in ${\mathrm{mm}}^{-1}$
	Probe 1	Probe 2	Probe 3	Probe 4	All probes combined
0.03	0.35 (0.32 to 0.39)	0.38 (0.33 to 0.42)	0.45 (0.42 to 0.48)	0.41 (0.37 to 0.45)	0.40 ($\pm 0.05$)
6.50	3.45 (3.35 to 3.53)	3.54 (3.50 to 3.60)	3.74 (3.68 to 3.78)	3.73 (3.60 to 3.85)	3.62 ($\pm 0.14$)
11.40	4.95 (4.92 to 4.98)	5.05 (5.02 to 5.09)	5.05 (5.00 to 5.09)	5.14 (5.11 to 5.21)	5.05 ($\pm 0.07$)
17	5.52 (5.47 to 5.60)	5.59 (5.52 to 5.68)	5.82 (5.81 to 5.83)	5.97 (5.91 to 6.13)	5.72 ($\pm 0.19$)
22.70	5.85 (5.73 to 6.05)	5.78 (5.76 to 5.80)	6.11 (6.01 to 6.20)	6.19 (6.12 to 6.23)	5.98 ($\pm 0.19$)