ISO   f/stop
25   1.4 2 2.8 4 5.6 8 11 16 22
50   2 2.8 4 5.6 8 11 16 22 32
100   2.8 4 5.6 8 11 16 22 32 44
200   4 5.6 8 11 16 22 32 44 64
400   5.6 8 11 16 22 32 44 64 88
800   8 11 16 22 32 44 64 88 128
1600   11 16 22 32 44 64 88 128 176
Subject Q Shutter Speed
Full Moon 8 1/4000 1/2000 1/1000 1/500 1/250 1/125 1/60 1/30 1/15
Umbrela Contact
Gibbous Moon
7 1/2000 1/1000 1/500 1/250 1/125 1/60 1/30 1/15 1/8
Umbrela: Mag=0.25
Quarter Moon
6 1/1000 1/500 1/250 1/125 1/60 1/30 1/15 1/8 1/4
Umbrela: Mag=0.50
Thick Crescent Moon
5 1/500 1/250 1/125 1/60 1/30 1/15 1/8 1/4 1/2
Umbrela: Mag=0.75
Thin Crescent Moon
4 1/250 1/125 1/60 1/30 1/15 1/8 1/4 1/2 1 sec
Totality: L=4 -3 1/2 1 sec 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min
Totality: L=3 -5 2 sec 4 sec 8 sec 15 sec 30 sec 1 min 2 min 4 min 8 min
Totality: L=2 -7 8 sec 15 sec 30 sec 1 min 2 min 4 min 8 min 15 min 30 min
Totality: L=1 -9 30 sec 1 min 2 min 4 min 8 min 15 min 30 min
Totality: L=0 -11 2 min 4 min 8 min 15 min 30 min

Exposure Formula t=f2/(Ix2Q)
where: t=exposure time (sec)
where: f=f/stop
where: I=ISO film speed
where: Q=brightness exponent
by: F.Espenak
ref: Origional image
ref: Origional Page