Nikon SB 20 - Setting Lens Aperture for Autofocus

2. Set aperture.
With Nikon F-401 /N4004, use camera's aperture
dial. Don't forget to lock lens
at minimum position. For other flash operations, set as follows:
For programmed TTL operation,
set to smallest le ns
aperture (largest I-number) and lock the lens apertur e.
(For detai ls, see the le ns instruc ti on manual).
Lens
only
F-5011
N2020
with
TC·16A
Lens maximum
aperture
fl2.8
or laster
Slower than
1/2 .8
1/1.4 or 1/1 .2
1/1 .8,1/2, fl2.5 or 1/2.8
Aperture setting
1/2 .8 or larger I·number
(1/28,1/4,1/5.6, etc)
115 .6 or larger I-number
(1/56,1/8,1/11, etc)
1/2 or larger I-number
(1/2 ,1/2.8 ,1 /4, etc)
1/4 or la rger I-number
(1/4,1/5.6, 1/8, etc)
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