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LOGARITHMIC GRAY SCALE TEST CHART YE153/TE153
Brand:Sineimage/Esser
Model:YE153/TE153
Dimension:Custermerizable
Type:Reflectance/Transmission
Two 11-graduated counter current gray scales are arranged on a gray background (D=0.75), the gray scale being graduated logarithmically.
Related to the densities of the gray scales: gamma = 0.45
Related to the reflectance values (brightness): gamma = 2.2 , that being exactly the reciprocal value of gamma = 0.45.
The output signal of an optimally gamma-corrected camera yield two 11-graduates counter current linear step signals. The contrast range of the gray scales is 40 : 1.
The values of the 11-graduated gray scale are as follows:
Step | Density | Reflectance in % |
1 | 0.05 | 89 |
2 | 0.13 | 74 |
3 | 0.22 | 60 |
4 | 0.32 | 48 |
5 | 0.43 | 37 |
6 | 0.55 | 28 |
7 | 0.69 | 20 |
8 | 0.88 | 13 |
9 | 1.06 | 8 |
10 | 1.31 | 5 |
11 | 1.65 | 2 |
The density values are based on BaSo4 = 0. Two black fields and a white field are located between the gray scales, the density of the black filed is D > 2.4 (reflectance < 0.5 %). The density of the white filed is D = 0.05 (reflectance = 89.9 %).