Snímek 5235

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    : 2006:02:26 18:15:23
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5235.pgm)
# Focal length : 10.7mm  (35mm equivalent: 72mm)
# 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   -68   -64   -65   -67        -4.89    -2.68    -4.37    -3.45  
 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    50    51    51    46         3.59     2.12     3.00     2.63  
 99   143   170   169    99         10.3     7.04     6.45     8.17  
100 15869 15866 15866 15867         1.14E3    659     1.03E3    827  
# flux from 0.186*0.61 sr ( 2.44E-7 sr/4px) is  0.125 lx ( 0.186 lx tilewise);
# tilewise luminance  0.895 cd/m2 with rel. SD  210 % (summing pixels below 15850 and with non-zero green: there is 61.4 % of them)
# Fuji Devignetting: 2 # dark frame dark/5238.pgm subtracted from all values
# Red  average=  19.3  minimum= -145  maximum=15869   over 15850: 165 zero: 36.7 %
# GrUp average=  24.6  minimum= -140  maximum=15866   over 15850: 155 zero: 38.8 %
# GrDw average=  23.9  minimum= -145  maximum=15866   over 15850: 158 zero: 38.4 %
# Blue average=  14.9  minimum= -176  maximum=15867   over 15850: 152 zero: 39.6 %

End of results of "raw2lum" (version 1.22) with parameters:
  -c fuji -fa -d dark/5238.pgm -nh -nt -i 5235.txt -t 118 -s71:76 pgm/5235.pgm

Just points with luminances over 40 and below 6.0E2 cd/m2. In grid tiles, flux densities from these points and tiles are given.
# Date/Time    : 2006:02:26 18:15:23
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5235.pgm)
# Focal length : 10.7mm  (35mm equivalent: 72mm)
# 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   -68   -64   -65   -67        -4.89    -2.68    -4.37    -3.45  
 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    50    51    51    46         3.59     2.12     3.00     2.63  
 99   143   170   169    99         10.3     7.04     6.45     8.17  
100 15869 15869 15869 15869         1.14E3    659     1.03E3    827  
# flux from 2.75E-4 sr ( 2.44E-7 sr/4px) is  0.0319 lx (points with luminances over   40    and below  6.0E2 )
# Fuji Devignetting: 2 # dark frame dark/5238.pgm subtracted from all values
# Red  average=2406.4  minimum= -122  maximum=15869   over 15850: 764938
# GrUp average=2705.9  minimum= -126  maximum=15866   over 15850: 764928
# GrDw average=2639.9  minimum= -128  maximum=15866   over 15850: 764931
# Blue average=1876.4  minimum= -125  maximum=15867   over 15850: 764925

End of results of "raw2lum" (version 1.21) with parameters:
  -c fuji -ft -d dark/5238.pgm -sm100 -nh -L40 -U600 -i 5235.txt -e 5235.eps -n 5235.ppm -t 118 -s71:76 pgm/5235.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.