Print-friendly version
Sensor Cleaning
Eventually you will find that photographs you have taken with your
DSLR will start to show artefacts. These may make themselves apparent
as slightly darker patches on the image or is individual black or
brown spots that are quite visible to the naked eye. Even more
annoying are those that only make themselves apparent on certain
photographs, when photographing a white sky for instance. If you
suspect that your camera does have dust or dirt on the sensor (it
will happen at some time in your cameras life) a quick way to test
(assuming your camera does not have a built in test mode) is to point
your camera at a plain white wall (or a large sheet of white paper)
in a well lit (even lighting is important) room, set the focus to
infinity, and take a picture. This will reveal any hidden nasties
(often referred to by photographers the world over as “dust
bunnies”) that could rear their ugly heads on your prized snaps.
Some camera manufacturers have gotten wise to the idea of sensor
cleaning and actively encourage it, initially they were wary of
encouraging home users to tinker with the inner workings of their
cameras but it is acknowledged as a necessity when you own a DSLR
unless you want to run up a large bill (and potentially damage your
camera) shipping it to an external cleaning firm or back to the
manufacturer every time it gets dirty. Many manufacturers now include
a variety of self cleaning modes in their cameras, some even produce
sensors that gently vibrate when you turn the camera on in an effort
to shake off dust and loose particles. However often these attempts
are in vain and you have to resign yourself to the fact that
eventually you will have to physically clean your own sensor.
There are many methods that various companies and photographers
will recommend, and before you attempt any please be warned, the
Photography Website is not liable for any damage you do to your
camera (or yourself, friends, loved ones or the pet cat after you
damage your camera), consider yourself warned! Always read your
cameras manual as many manufacturers do not recommend touching the
sensor or in some case even cleaning the sensor yourself.
The most common method (and most recommended by manufacturers) is
using a blowing implement of some kind to direct a gentle stream of
air over the sensor. Do not attempt to do this with cans of
compressed air or anything under pressure! You will almost certainly
damage your camera if you do, the only air that you should blow into
the camera comes from a blower bulb (think the strength of someone
gently breathing). Hold the bulb no further into the camera than the
lens mount and use it to blow air over the sensor. Unfortunately this
technique can sometimes actually redistribute the dust across the
surface of your sensor rather than dislodge it, however it is worth
trying in the first instance, it may just dislodge those annoying
dust bunnies. If you are unable to get rid of the dust spots using a
blower bulb then you may have to manually clean your sensor, again
this can be dangerous if done incorrectly and could result in the
destruction of your camera, so please do not attempt it unless you
are absolutely confident.
Fortunately you can now purchase “sensor swabs” designed
specifically for cleaning your DSLR sensor, or a “sensor brush”.
These will contain full instructions that you should follow, however
they usually involve cleaning the brush with compressed air and
wiping in one sweep across the sensor, and then cleaning the brush
again after every stroke to ensure you are not simply spreading the
dust around. When using sensor swabs they often require dampening
with a non-water based cleaning solution (ensure you purchase some
just for sensor cleaning) or you can used an alcohol based cleaner
such as methanol. Unfortunately if you are overzealous with your
cleaning fluid you can often leave streaks on the sensor with swabs,
however they are often vital for removing the more stubborn artefacts
caused by things such as pollen (since pollen is moist it will often
be harder to remove than regular household dust).
It is worth noting that occasionally you can get dust that is
trapped beneath the filters or even beneath the filters and the
sensor itself (when we talk about cleaning the sensor we do not refer
to the actual sensor but the filter that sits over the sensor, as a
home user we do not have the tools or expertise to access the sensor
directly) and nothing can be done about this other than send your
camera back to the manufacturer for servicing. Fortunately this is a
rare occurrence, however if you are unable to remove a stubborn dust
spot please resist the temptation to scrub or rub hard at the face of
the sensor, you will simply damage it and probably void your
warranty. And if you are at all lacking in confidence or unsure of
how to approach cleaning your sensor you should always send it back
to your manufacturer for a service.
|