Snímek 5137

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 20:24:03
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5137.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   -71   -67   -68   -69        -5.10    -2.80    -4.50    -3.61  
 10   -35   -32   -33   -34        -2.51    -1.35    -2.22    -1.76  
 50     0     0     0     0         0.00     0.00     0.00     0.00  
 90    40    38    39    38         2.87     1.60     2.48     2.04  
 99    94   119   120    85         6.75     4.96     5.54     5.59  
100 16365 16379 15912 15906         1.18E3    670     1.04E3    847  
# flux from 0.654*0.52 sr ( 8.59E-7 sr/4px) is  0.134 lx ( 0.227 lx tilewise);
# tilewise luminance  0.311 cd/m2 with rel. SD  318 % (summing pixels below 15850 and with non-zero green: there is 51.9 % of them)
# Fuji Devignetting: 1 # dark frame dark/5119.pgm subtracted from all values
# Red  average=   6.2  minimum= -146  maximum=16365   over 15850:  31 zero: 44.1 %
# GrUp average=   9.6  minimum= -141  maximum=16379   over 15850:  36 zero: 48.3 %
# GrDw average=   9.2  minimum= -146  maximum=15912   over 15850:  35 zero: 47.9 %
# Blue average=   5.3  minimum= -143  maximum=15906   over 15850:  34 zero: 46.4 %

End of results of "raw2lum" (version 1.22) with parameters:
  -c fuji -fa -d dark/5119.pgm -nh -nt -i 5137.txt -t 118 -s71:76 pgm/5137.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 20:24:03
# Resolution   : 1280 x 960 in jpeg (1424x1076 in pgm/5137.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   -71   -67   -68   -69        -5.10    -2.80    -4.50    -3.61  
 10   -35   -32   -33   -34        -2.51    -1.35    -2.22    -1.76  
 50     0     0     0     0         0.00     0.00     0.00     0.00  
 90    40    38    39    38         2.87     1.60     2.48     2.04  
 99    94   119   120    85         6.75     4.96     5.54     5.59  
100 16379 16379 16379 16379         1.18E3    680     1.07E3    854  
# flux from 5.40E-4 sr ( 8.59E-7 sr/4px) is  0.0274 lx (points with luminances over   25    and below  5.0E2 )
# Fuji Devignetting: 1 # dark frame dark/5119.pgm subtracted from all values
# Red  average=1128.5  minimum= -137  maximum=16365   over 15850: 765448
# GrUp average=1283.1  minimum= -132  maximum=16379   over 15850: 765453
# GrDw average=1349.6  minimum= -141  maximum=15912   over 15850: 765452
# Blue average=1068.9  minimum= -136  maximum=15906   over 15850: 765451

End of results of "raw2lum" (version 1.21) with parameters:
  -c fuji -ft -d dark/5119.pgm -sm100 -nh -L25 -U500 -i 5137.txt -e 5137.eps -n 5137.ppm -t 118 -s71:76 pgm/5137.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.