How to translate log density readings to percent?

Sorry if this is too basic (I know little about densitometers):

Let's assume I made the following readings:

dmin = 0.12 ( dmin' = 0 )
reading1 = 0.42 ( reading1' = 0.30 )
reading2 = 0.96 ( reading2' = 0.84 )
dmax = 1.45 ( dmax' = 1.33 )

Numbers in parenthesis are net densities (reading1' = reading1 - dmin).

Is it correct to convert these readings using the following method?

d = log ( 1 / R )

d: log density
R: reflectance (%)

=>

R = 1 / ( 10 ^ d )

d' R' 1 - R' Mapped
1 - R'
0,00 100,00 0,00 0,00
0,30 50,12 49,88 52,33
0,84 14,45 85,55 89,74
1,33 4,68 95,32 100,00

If not, what is the correct method to convert log density readings to
percent?

TIA,
Loris.
Received on Tue Sep 7 04:16:13 2004