Page 161 - (DK) Advanced Photography Guide

IM AGE ENH A N CEMEN T 159

Sensor dust CLEANING A SENSOR
Digital sensors have an electrical charge that Sticky or wet particles such as pollen have to be removed from
attracts dust and other small particles, which stick the sensor using sensor cleaning tools. The simplest way is to
to the sensor. This is not a problem for cameras use a sensor swab with a few drops of sensor cleaning fluid on
with a fixed lens, but DSLRs and CSCs both let dust it. Gently wipe the swab across the sensor, once only on each
into the camera body every time you change the side, to remove the particles. DSLRs usually have a mirror
lockup function specifically for cleaning the sensor.
lens. Over time, dust can build up on the sensor,
becoming visible in your photos as small, diffuse
gray disks, particularly in light areas or on even APERTURE AND LENS TYPE
tones, as in the sky. CSCs are more prone to The visibility of dust is affected by the lens and aperture you
problems with dust than DSLRs, as their sensors use. The smaller the aperture, the more visible the dust. If you
are not protected by a shutter. There are several use large apertures and long-focal-length lenses, you may never
see dust in your photos. Landscape photographers have to clean
solutions to sensor dust, some of which are applied their sensors regularly because they work in dusty environments
when you shoot and others in postproduction. and tend to use small apertures to maximize depth of field.

AUTOMATIC REMOVAL DIGITAL REMOVAL

Most modern DSLRs and CSCs have automatic dust removal Dust can be removed in postproduction using a number of
systems that physically shake the sensor, making dust fall off. tools. The simplest is the Spot Healing Brush, with which you
These systems can be set to activate when the camera is turned “paint” over the dust. The software then automatically replaces
on or off, or as necessary after selecting the sensor cleaning it with patches of color and texture similar to the area around
option. The dust removal cycle is a much easier task than the brush. The Clone Stamp tool is more complex but gives you
cloning out dust spots in postproduction. better control over what you patch in to replace the dust.

ADJUSTMENT BRUSH
Lightroom’s Adjustment Brush
tool enables you to paint local
adjustments onto your photo.
You can create two brushes
and alternate them to vary the
2 Size, Feather, and Flow. The
brushes also can be set to
Erase to remove adjustments.
1
3 1 A brush is shown by a
pin. Select it to move or
delete an adjustment.

2 Size alters the brush’s
dimensions. Feather sets
how soft the edge is.

Brush : A B Erase 3 The Flow slider sets how
quickly the effect builds
Size 29.4
up. A low Flow value lets
Feather 78 you increase it gradually.
Flow 100

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