Snímek 5152

původní zesvětlený barevně kódovaný

a ještě s vloženou mřížkou s údaji:

(údaj uprostřed políček mřížky je medián surových hodnot zelených pixelů, údaj dole je jas políčka dělený jednou kandelou na metr čtvereční).
# Date/Time    : 2006:02:24 21:40:06
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5152.pgm)
# Focal length :  5.7mm  (35mm equivalent: 39mm)
# CCD width    : 5.32mm
# Exposure time: 0.008 s  (1/125)
# Aperture     : f/2.8
# ISO equiv.   : 200

# Selected image percentils         L=(1.730*0.35*R+1.000*0.65*G+1.570*0.00*B)* 0.0415
# %    R     G1    G2    B readings  R        G        B        L / cd/m2
  1   -70   -66   -66   -69        -5.03    -2.74    -4.50    -3.54  
 10   -33   -29   -29   -32        -2.37    -1.20    -2.09    -1.61  
 50     0     0     0     0         0.00     0.00     0.00     0.00  
 90    55    62    62    51         3.95     2.57     3.32     3.06  
 99   151   226   226   136         10.8     9.38     8.87     9.90  
100 15992 15989 15989 15990         1.15E3    664     1.04E3    834  
# flux from 0.654*0.61 sr ( 8.59E-7 sr/4px) is  0.465 lx ( 0.688 lx tilewise);
# tilewise luminance  0.948 cd/m2 with rel. SD  198 % (summing pixels below 15850 and with non-zero green: there is 60.6 % of them)
# Fuji Devignetting: 1 # dark frame dark/5154.pgm subtracted from all values
# Red  average=  18.8  minimum= -158  maximum=15992   over 15850: 111 zero: 37.4 %
# GrUp average=  28.6  minimum= -148  maximum=15989   over 15850: 139 zero: 40.0 %
# GrDw average=  28.5  minimum= -162  maximum=15989   over 15850: 135 zero: 38.9 %
# Blue average=  17.6  minimum= -143  maximum=15990   over 15850: 137 zero: 40.0 %

End of results of "raw2lum" (version 1.22) with parameters:
  -c fuji -fa -d dark/5154.pgm -nh -nt -i 5152.txt -t 118 -s71:76 pgm/5152.pgm

Just points with luminances over 25 and below 5.0E2 cd/m2. In grid tiles, flux densities from these points and tiles are given.
# Date/Time    : 2006:02:24 21:40:06
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5152.pgm)
# Focal length :  5.7mm  (35mm equivalent: 39mm)
# CCD width    : 5.32mm
# Exposure time: 0.008 s  (1/125)
# Aperture     : f/2.8
# ISO equiv.   : 200


# Selected image percentils         L=(1.730*0.35*R+1.000*0.65*G+1.570*0.00*B)* 0.0415
# %    R     G1    G2    B readings  R        G        B        L / cd/m2
  1   -69   -65   -66   -67        -4.96    -2.72    -4.37    -3.50  
 10   -32   -28   -29   -31        -2.30    -1.18    -2.02    -1.57  
 50     0     0     0     0         0.00     0.00     0.00     0.00  
 90    55    62    62    51         3.95     2.57     3.32     3.06  
 99   151   227   227   136         10.8     9.43     8.87     9.92  
100 15992 15992 15992 15992         1.15E3    664     1.04E3    834  
# flux from 7.97E-4 sr ( 8.59E-7 sr/4px) is  0.0631 lx (points with luminances over   25    and below  5.0E2 )
# Fuji Devignetting: 1 # dark frame dark/5119.pgm subtracted from all values
# Red  average=1756.3  minimum= -118  maximum=15992   over 15850: 765104
# GrUp average=2214.3  minimum= -125  maximum=15989   over 15850: 765132
# GrDw average=2204.1  minimum= -125  maximum=15989   over 15850: 765128
# Blue average=1891.2  minimum= -124  maximum=15990   over 15850: 765130

End of results of "raw2lum" (version 1.21) with parameters:
  -c fuji -ft -d dark/5119.pgm -sm100 -nh -L25 -U500 -i 5152.txt -e 5152.eps -n 5152.ppm -t 118 -s71:76 pgm/5152.pgm

skala jasu / 1 
cd/m<sup>2</sup>
Logaritmická škála jasů (jednotkou je kandela na metr čtvereční, nazývaná též nit) – intenzity osvětlení sněhu v luxech dostanete vynásobením jasu v nitech koeficientem 3,6. U intenzit osvětlení lesní stěny je takový koeficient 20 až 40.