Each wedge is different slightly form each other. You set the 810 for the values on the wedge. The step that is used to calibrate (CAL high) is about 3.00 density. The CAL low is nothing. There are steps of 0.27, 1.50 and 3.75 to check for linearity.
I have a Stouffer step wedge with known densities and I'll use it. I assume I can set the 0.27, 1.50 and 3.7 densities with my step wedge with similar densities also.
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