Operating Instructions

ASA/ISO speed Slowest shutter speed (sec.)
6400 1/60
3200 (4000) 1/30
1600 1/15
800 1/8
400 1/4
200 (160) 1/2
100 (80) 1
50 (64) 2
25 4
12 8
Table
Slowest shutter speed at full aperture with any lens
How to read the EV chart
• Full-aperture metering
Example: Lens maximum aperture f/1.4
ASA/ISO film speed 100
Workinq aperture f/5.6
By referring to the f/1.4 column in Section A and the EV values indicated for ASA/ISO 100 in Section D, you
will find that the EV range for an f/1.4 lens at ASA/ISO 100 is 1 to 18. Now, refer to Section B and single out the
f/5.6 indication for ASA/ISO 100. Go diagonally down until the protruding line intersects with Section C's
vertical line for the shutter speed of 8 sec. (the F3 High-Eyepoint camera's slowest shutter speed). From this
point of intersection, follow the horizontal line that leads to Section D's EV value for ASA/ISO 100, and you will
obtain an EV value of 2. Start again from the f/5.6 indication for ASA/ISO 100 in Section B, and go down
diagonally until the protruding line intersects with Section C's vertical line for the shutter speed of 1/2000 sec.
(the F3 High-Eyepoint camera's fastest shutter speed) this time. Then follow the horizontal line that leads to
Section D's EV value for ASA/ISO 100, and you will get a reading ot EV 16. This means that an f/stop of f/5.6 at
ASA/ISO 100 and a shutter speed of from 8 to 1/2000 sec. has an effective EV range of 2 to 16, which is well
within the F3 High-Eyepoint camera's metering range ot EV 1 to EV 18. The area encompassed by the heavy
lines in Section C demonstrates a metering range for full aperture method using an f/1.4 lens and ASA/TSO 100
film.
• Stop-down metering
Example: ASA/ISO film speed 100
Stopped-down aperture f/8
The procedure is the same. The f/8 column in Section A and the EV values indicated for ASA/ISO 100 in Section
D will show you that the EV range for f/8 is 6 to 23. Refer now to Section B and single out f/8 at ASA/ISO 100.
Go diagonally down until the protruding line intersects with Section C's vertical line for the shutter speed of 8
sec. From this point of intersection, follow the horizontal line that leads to Section D's EV value for ASA/ISO
100, and you will obtain an EV reading of 3. This means that an f/stop of f/8 at ASA/ISO 100 and a shutter speed
of 8 sec. give an EV value outside the metering range. To find out the slowest shutter speed usable, follow the f/8
indication for ASA/ISO 100 in Section B diagonally down until it intersects the horizontal line in Section C that
leads to Section D's EV value of 6 for ASA/ISO 100, and you will find that the slowest shutter speed usable is 1
sec. In other words, at f/8 and ASA/ISO 100, the available shutter speed range that is within the metering range is
from 1 to 1/2000 sec., which has an effective EV range of 6 to 17 (indicated by the broken line in Section
C)—well within the metering range.