Snímek 5151

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 21:34:47
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5151.pgm)
# Focal length :  5.7mm  (35mm equivalent: 39mm)
# CCD width    : 5.32mm
# Exposure time: 0.125 s  (1/8)
# 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)* 0.00266
# %    R     G1    G2    B readings  R        G        B        L / cd/m2
  1   -55   -46   -47   -56        -0.253   -0.124   -0.234   -0.169 
 10   -11     0     0   -12        -0.0506   0.00    -0.0501  -0.0177
 50    45    62    62    40         0.207    0.165    0.167    0.180 
 90   510   768   769   428         2.34     2.04     1.79     2.15  
 99  2212  3315  3309  1877         10.2     8.80     7.83     9.28  
100 15992 15989 15989 15990         73.5     42.5     66.7     53.4  
# flux from 0.654*0.92 sr ( 8.59E-7 sr/4px) is  0.484 lx ( 0.517 lx tilewise);
# tilewise luminance  0.721 cd/m2 with rel. SD  176 % (summing pixels below 15850 and with non-zero green: there is 91.7 % of them)
# Fuji Devignetting: 1 # dark frame dark/5154.pgm subtracted from all values
# Red  average= 208.2  minimum= -148  maximum=15992   over 15850: 567 zero: 11.7 %
# GrUp average= 295.3  minimum= -138  maximum=15989   over 15850: 677 zero:  8.3 %
# GrDw average= 295.0  minimum= -135  maximum=15989   over 15850: 677 zero:  8.2 %
# Blue average= 178.7  minimum= -143  maximum=15990   over 15850: 607 zero: 14.1 %

End of results of "raw2lum" (version 1.22) with parameters:
  -c fuji -fa -d dark/5154.pgm -nh -nt -i 5151.txt -t 118 -s71:76 pgm/5151.pgm

Just points with luminances over 1.0 and below 25 cd/m2. In grid tiles, flux densities from these points and tiles are given.
# Date/Time    : 2006:02:24 21:34:47
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5151.pgm)
# Focal length :  5.7mm  (35mm equivalent: 39mm)
# CCD width    : 5.32mm
# Exposure time: 0.125 s  (1/8)
# 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)* 0.00266
# %    R     G1    G2    B readings  R        G        B        L / cd/m2
  1   -55   -46   -47   -56        -0.253   -0.124   -0.234   -0.169 
 10   -11     0     0   -12        -0.0506   0.00    -0.0501  -0.0177
 50    45    62    62    40         0.207    0.165    0.167    0.180 
 90   510   768   769   428         2.34     2.04     1.79     2.15  
 99  2212  3315  3309  1878         10.2     8.80     7.84     9.28  
100 15992 15989 15989 15992         73.5     42.5     66.7     53.4  
# flux from 0.101 sr ( 8.59E-7 sr/4px) is  0.378  lx (points with luminances over  1.0    and below   25   )
# Fuji Devignetting: 1 # dark frame dark/5154.pgm subtracted from all values
# Red  average= 936.7  minimum= -141  maximum=15992   over 15850: 648133
# GrUp average=1371.4  minimum= -127  maximum=15989   over 15850: 648243
# GrDw average=1370.6  minimum= -125  maximum=15989   over 15850: 648243
# Blue average= 766.0  minimum= -132  maximum=15990   over 15850: 648173

End of results of "raw2lum" (version 1.21) with parameters:
  -c fuji -ft -d dark/5154.pgm -sm100 -nh -L1 -U25 -i 5151.txt -e 5151.eps -n 5151.ppm -t 118 -s71:76 pgm/5151.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.