Focus Modes; Manual Focus With Electronic Rangefinder - Nikon F4 Instruction Manual

FOCUS MODES
The advanced autofocus system of the F4 works
even
under
extremely low-light conditions - as low as EV minus 1. The
Electronic Rangefinder operates for both autofocus and
manual focusing. Manual focusing can also be accomplished
using the clear matte screen or any optional screen with an
optical rangefinder. Normally, the Electronic Rangefinder's abil-
ity to detect focus is superior to the human eye. However, there
are certain subjects that cannot be focused upon in any way -
such as shiny metallic subjects, blank walls, etc. In this case, X
appears and autofocus with an alternate subject at the same
distance or manual adjustment by estimating the distance is
recommended.
Manual Focus with Electronic Rangefinder
Manual focus using the Electronic Rangefinder works with most
Nikon lenses, including AF Nikkor when operated manually.
(For a complete list of usable lenses, see lens compatibility
chart, page 86.) Lenses with a maximum aperture slower than
f/5.6 are not suitable for Electronic Rangefinder focusing,
even
though focus indicator LEDs appear. Focus using clear matte
field or change focusing screen to
J
type.
32
1. Set focus mode selector to M (manual). If lens has an A-M
switch, set to M.
2. Look inside viewfinder and position focus brackets on the
main subject.
Lightly press shutter release button.