Unbelievable Madagascar September 14–October 1, 2007
				India Wildlife: On the Trail of the Tiger November 7–24, 2007
				Angkor Wat & Bagan—Temples of Cambodia and Myanmar January 17–31, 2008

If you shoot a digital camera with interchangeable lenses, sooner rather than later you'll notice motes on your images—the effect of dust on your sensor. Frequent, obsessive cleaning is a fact of life with digital cameras. Fixed lens cameras deny dust entry to the chamber, so their sensors remain clean.

The dust doesn't accumulate on the sensor proper. A glass cover or filter protects the sensor from damage and dust. This glass can be scratched, smudged or otherwise degraded, and the first rule of cleaning is, "Do no harm."

Before touching the sensor glass with anything, try blasting it with air. The safest method involves a hand-squeezed blower bulb. It's hard to get enough force with small bulbs so look for one that fills the whole hand.

Some folks use compressed CO₂ gas. Ordinary compressed air contains propellants that accumulate on the sensor surface and must be avoided. Also, CO₂ cartridges designed for air rifles contain additives that may cause problems. CO₂ cartridges produce a very strong stream of air. While CO₂ gets the dust moving, it can also force it into inaccessible parts of the camera. Finally, CO₂ cartridges are not welcome on airplanes these days.

The Sensor Brush from Visible Dust of Canada is the most effective and easiest solution for removing dust and other particulates. Various sizes are available for use on different-sized sensors. The brushes are reusable and washable. To clean a sensor, blast the bristles with either condensed air or with puffs from a large bulb. This removes dust from the bristles and gives them a positive charge. Sweep across the sensor once, then blast the bristles again to clean and charge them before sweeping again. Repeat as needed. If the bristles acquire bits of gunk that blasting won’t remove, wash the brush with mild soap or isopropyl alcohol. (Don’t use methanol. It will destroy the bristles.)

Available in a variety of sizes, sensor brushes make it easy to clean digital sensors.

Moisture can create spots the brush can’t remove. Just breathing on the sensor transfers moisture. When this happens, a liquid solvent must be used.

I've always had a problem using swabs and liquids. With my lack of dexterity and inability to apply just the right amount of fluid, I end up with streaks that take many frustrating minutes to eradicate. Sensor Swabs, available from Photographic Solutions, minimize streaking. Shaped like miniature white brooms, the swabs allow for a precise application of cleaning solution. Each swab can be used twice. Sweep in one direction, which should cover half the sensor, and then sweep in the other direction with the other side of the swab so that both halves of the sensor receive one swipe. Larger sensors require two swabs. These are pricey gizmos. Use them only when air cleaning fails.

The "tools of the trade" for cleaning digital sensors. Shown here are a blower bulb, swabs and cleaning solution.

Visible Dust offers a cleaning system with a proprietary solvent called Sensor Clean which is applied with medical-grade cotton swabs. (Most swabs have powder on them to increase absorption, which will leave deposits on sensors and may scratch them.) In my experience, using the Sensor Clean solvent with Photographic Solutions' Sensor Swabs produces the smallest amount streaking—at least with my clumsy technique.

When you're ready to start cleaning, find a brightly-lit working space. Activate the cleaning protocol in your camera. This will open the shutter and swing the mirror out of the way, giving you access to the sensor surface. Remove the lens and hold the camera so the opening faces down. This may reduce the amount of dust landing on the sensor glass as you clean it, although a static charge on a recently-used sensor may attract more dust anyway. Move the nozzle of the bulb blower into the camera, taking care to avoid touching the glass with the nozzle. Squeeze vigorously a few times. After a visual inspection (a jeweler’s loupe can help), replace the lens. Don’t blow into the camera.

Visible Dust’s Sensor Brush accomplishes the same thing more easily and effectively.

The easiest way to check for dust after cleaning is to shoot a frame of a blue sky or any other absolutely uniform bright or mid-toned subject. Turn off the autofocus, and throw the lens out of focus manually. After downloading, bring the image up on your computer screen and blow it up to 100%. Look for dark flecks and globs on the screen. If any dust remained on the sensor, it will be easy to see. If air or brush cleaning fails after a few tries, use the Sensor Swabs or Sensor Clean.

Sensor cleaning may be the most annoying part of digital photography for many—including myself—but it will gladden the hearts of obsessives!