Fractional F-stops and Shutter Speeds

Aperture progressions in 1/3 stops - sixth root of two Aperture progressions in 1/2 stops - fourth root of two
0.7 0.707111 0.7 0.707111
+1/3 0.793703 +1/2 0.840903
+2/3 0.8909 1 1.00001  
1 1 +1/2 1.189222
+1/3 1.12246 1.4 1.414235
+2/3 1.259916 +1/2 1.681822
1.4 1.414206 2 2.00004
+1/3 1.587389 +1/2 2.378468
+2/3 1.781781 2.8 2.828498
2 1.999978 +1/2 3.363678
+1/3 2.244895 4 4.000119
+2/3 2.519805 +1/2 4.756981
2.8 2.828381 5.6 5.65705
+1/3 3.174744 +1/2 6.72742
+2/3 3.563523 8 8.000316
4 3.999912 +1/2 9.514055
+1/3 4.489742 11 11.31421
+2/3 5.039555 +1/2 13.45497
5.6 5.656699 16 16.00079
+1/3 6.349419 +1/2 19.0283
+2/3 7.126969 22 22.62864
8 7.999737 +1/2 26.9102
+1/3 8.979385 32 32.00188
+2/3 10.079 +1/2 38.05696
11 11.31327 45 45.25772
+1/3 12.6987 +1/2 53.82093
+2/3 14.25378 64 64.00439
16 15.9993 +1/2 76.11466
+1/3 17.95857 90 90.51631
+2/3 20.15778 +1/2 107.6429
22 22.6263 128 128.01
+1/3 25.39712
+2/3 28.50725
32 31.99825
+1/3 35.91675
+2/3 40.31512
45 45.25211
+1/3 50.79368
+2/3 57.01388
64 63.9958
+1/3 71.83272
+2/3 80.62936
90 90.50323
+1/3 101.5863
+2/3 114.0265
128 127.9902
Shutter Speed progressions in 1/3 stops - third root of two Shutter Speed progressions in 1/2 stops - square root of two
30' 30 30' 30
+1/3 23.81104 +1/2 21.21326
+2/3 18.89885 15' 15.00008
15' 15.00004 +1/2 10.60668
+1/3 11.90555 8' 8 * - break
+2/3 9.449447 +1/2 5.656868
8' 8 * - break 4' 4.00002
+1/3 6.349609 +1/2 2.828448
+2/3 5.039693 2' 2.00002 '1/over'
progression
4' 4.00001 +1/2 1.414231
+1/3 3.174813 1' 1.000015 1
+2/3 2.519853 +1/2 0.707119 1.41421
2' 2.00001 1/2 0.50001 1.99999
+1/3 1.58741 '1/over'
progression		 +1/2 0.353561 2.828406
+2/3 1.259929 1/4 0.250006 3.99996
1' 1.000007 1 +1/2 0.176782 5.656783
+1/3 0.793707 1.25992 1/8 0.125004 7.999879
+2/3 0.629966 1.587398 +1/2 0.088391 11.31351
1/2 0.500005 1.999995 1/15 0.062502 15 * - break
+1/3 0.396855 2.519834 +1/2 0.044196 21.21315
+2/3 0.314984 3.174789 1/30 0.031251 29.99985
1/4 0.250003 3.99998 +1/2 0.022098 42.42609
+1/3 0.198428 5.039655 1/60 0.015626 59.9994
+2/3 0.157492 6.349562 +1/2 0.011049 84.85175
1/8 0.125002 7.99994 1/125 0.007813 125 * - break
+1/3 0.099214 10.07928 +1/2 0.005525 176.7763
+2/3 0.078746 12.69909 1/250 0.003906 249.9987
1/15 0.062501 15 * - break +1/2 0.002762 353.5507
+1/3 0.049607 18.8988 1/500 0.001953 499.995
+2/3 0.039373 23.81098 +1/2 0.001381 707.0979
1/30 0.031251 29.99993 1/1000 0.000977 999.9849
+1/3 0.024804 37.79751 +1/2 0.000691 1414.189
+2/3 0.019687 47.62183 1/2000 0.000488 1999.96
1/60 0.015625 59.9997 +1/2 0.000345 2828.363
+1/3 0.012402 75.59482 1/4000 0.000244 3999.899
+2/3 0.009843 95.24343 +1/2 0.000173 5656.698
1/125 0.007813 125 * - break 1/8000 0.000122 7999.758
+1/3 0.006201 157.49
+2/3 0.004922 198.4248
1/250 0.003906 249.9994
+1/3 0.0031 314.9792
+2/3 0.002461 396.8486
1/500 0.001953 499.9975
+1/3 0.00155 629.9569
+2/3 0.00123 793.6952
1/1000 0.000977 999.9925
+1/3 0.000775 1259.911
+2/3 0.000615 1587.387
1/2000 0.000488 1999.98
+1/3 0.000388 2519.815
+2/3 0.000308 3174.765
1/4000 0.000244 3999.95
+1/3 0.000194 5039.617
+2/3 0.000154 6349.514
1/8000 0.000122 7999.88

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