Pentax ZOOM 60-X Operating Manual page 19

D Recompose the picture while keeping the shutter
release button depressed halfway, and then fully
depress the shutter release button to take a picture.
Note:
• Taking your finger off the shutter release button in its
halfway position cancels focus lock .
Hard-to-autofocus subjects
Like many other autofocus cameras, this camera's
autofocus system is highly precise, but it may not
focus exactly as you wish on certain subjects. In
such cases, use the focus*lock technique on a
subject which is both near the actual one and at an
equal distance from the lens.
Subjects which are hard to autofocus include:
1. Black objects, like hair, which don't reflect much
light
(and therefore don't reflect infrared autofocus
beams).
2. Wire netting, latticework, iron exercise-bars, etc.
3. Flickering light sources such as neon signs,
fluorescent lamps, TV images, sunlight coming
through trees, etc., and subjects illuminated by
these light sources.
4. Glossy and reflective surfaces like glass, mirrors,
car bodies, etc.
5. Fast-moving objects, like trains In motion.
6. Water jets, water surface, smoke, flame, fireworks,
etc., which have no distinct or consistent form, or
a subject in mist.