Cleaning your camera and sensor: dust, airport grime and gear care

The evening flight arrives in perfect light, the burst is in the bag, the focus is spot on – and then at the computer you see three gray spots in the blue sky, in exactly the same place on every picture. Sensor dust is one of the typical annoyances in aircraft photography because our subjects so often stand against a smooth sky. On top of that comes what the airport environment brings: wind over the open field, sand whirled up on dirt tracks, spray and temperature swings between the fence and the car. This guide shows you how to clean your camera and sensor without risking anything, how to care for lenses and which routine makes sense after hard spotting days.

The short answer

Cleaning the sensor means, in nine out of ten cases: do a dust test, run the automatic cleaning, blow off the rest with a blower. Only if spots still remain does wet cleaning with swabs come into play – yourself or at a service center. Compressed air spray, a brush on the sensor and cleaning in the wind at the fence are off limits.

Important to understand: what you call the “sensor” is, on most cameras, actually a filter stack made of glass in front of the actual image sensor. Dust sits on this glass, a little distance from the light-sensitive layer. That is why it appears as a soft haze at wide apertures and as a sharply outlined dot at small apertures.

Why spotters see sensor dust especially often

In aircraft photography, several factors come together that make dust visible:

• Smooth sky as background. A blue or light gray sky is the perfect test surface. Every spot that disappears in the clutter of a subject with texture jumps out here immediately.
• Small apertures. If you stop down to f/8 to f/11 in bright light, you make dust sharper and darker than at wide open.
• Lens changes outdoors. At the fence, you quickly switch between a telephoto for landings and a shorter focal length for taxiing shots. Every change in the wind opens the camera interior to dust, pollen and sand.
• The environment itself. Spotting locations are often on dirt tracks, earth banks or gravel areas. Add spray after rain and, at some spots, the fine film of grime that operations around the runways put in the air.

A speck of dust does not get any worse because of this than elsewhere – you simply see it more often. How to find and retouch spots in pictures you have already taken is explained in the article Finding and removing sensor spots in the sky.

Step 1: The dust test

Before you clean anything, you check whether there is anything to do at all. It takes a minute.

A detail that tends to confuse: the image on the sensor is upside down. A spot that is at the top of the photo is therefore at the bottom on the sensor. For the blower, that hardly matters; for targeted wet cleaning, it does.

Step 2: Automatic sensor cleaning

Almost all current mirrorless and DSLR cameras have built-in sensor cleaning. The filter glass in front of the sensor is set vibrating very quickly so that loose particles fall off and – depending on the model, for example onto an adhesive strip – are caught. Many cameras do this automatically on request when switching on or off, and the cleaning can usually also be started manually in the settings menu.

Here is how to use it sensibly:

• Hold the camera upright so that loosened particles fall downward.
• Once is enough. Canon points out that repeating it several times in a row has hardly any additional effect.
• Test again afterward. Only if the dust test still shows spots do you continue.

Stuck-on particles, pollen that sticks because of moisture, or oil splatter from inside the camera are not removed by the vibration.

Step 3: Blower – used correctly

The blower is the most important tool for sensor care. Buy a large, simple rubber blower without a brush attachment. The manufacturers’ manuals are clear here: Canon expressly recommends a blower without a brush because a brush can scratch the sensor, and warns against inserting the tip into the camera deeper than the mount.

Here is how to proceed:

1. Choose a clean, windless place – indoors, not at the fence and not in an open trunk.
2. Charge the battery fully. On DSLRs, in manual cleaning mode the mirror flips up and the shutter opens. If the power fails in the meantime, the shutter closes and can be damaged along with the mirror. On mirrorless cameras, the sensor is usually directly exposed after the lens is removed.
3. Activate the manual cleaning mode if your camera has one, and remove the lens.
4. Hold the camera with the mount facing down. This way, the blown-off dust falls out instead of deeper into the body.
5. Blow with a few firm squeezes, the tip just in front of the mount, without touching the sensor.
6. Switch the camera off, put on the lens or cap, test again.

Some mirrorless models offer a setting that places a shutter curtain or cover in front of the sensor when switched off. A look at the manual is worthwhile: for lens changes at the fence, this function is worth its weight in gold.

Step 4: Wet cleaning

If a spot remains after the blower, it is stuck – often a dried droplet, pollen or a tiny oil splatter. Now you have two options: wet-clean yourself or have the service do it.

If you clean it yourself, a few basic rules apply. Use ready-made sensor swabs whose width fits your sensor, and a cleaning fluid expressly intended for sensors. One or two drops are enough; a dripping swab leaves streaks at the edges. Pull the swab across the surface in one stroke without pressure, turn it and pull back in the opposite direction. After that it is used up – every further pass needs a fresh swab. Test again at the end.

Caring for lenses: front element, rear element, mount

A big telephoto lens takes more at the fence than the sensor: raindrops, fingerprints from handling the lens hood, dust from the wind. The order is always the same – first dry, then wet.

Area	Typical dirt	Tool	What to watch for
Front element	dust, drops, fingerprints	blower, brush, microfiber cloth, lens cleaner	put cleaner on the cloth, never spray directly onto the lens
Rear element	dust, fingerprints	blower, lens tissue	often forgotten – dirt here has more effect than in front
Mount and contacts	dust, abrasion	blower, dry cloth	keep contacts clean and dry, no liquid
Lens hood	dust inside, spray	brush, damp cloth	keep the inside clean, otherwise flare and crumbs
Filter	streaks, drops	like the front element	use protective filters only in good quality

A few practical points:

• Blow first, then wipe. If you rub grains of sand over the coating with a cloth, you grind them into the surface.
• Circular, from the inside out. This way you push the dirt to the edge instead of spreading it.
• Keep cloths clean. A microfiber cloth loose in a jacket pocket collects dust itself. Keep it in a small pouch and wash it regularly without fabric softener.
• Take the rear element seriously. It sits close to the sensor, and fingerprints there cost considerably more contrast than in front.

Whether a protective filter in front of the front element makes sense is a popular debate among spotters. With lots of spray or sand, it can protect the lens, but cheap glass costs contrast – especially at long focal lengths. You can find more on filters in the article Polarizing and other filters, and on choosing a focal length in the guide Lens for plane spotting.

Care after rain, cold and dusty days

Airports are open areas: the wind has a free run, and weather changes hit you without cover. Good care therefore starts at the spot.

After rain and spray

Dab the body and lens dry with an absorbent cloth while still outside, before water runs into seams. At home, let the camera and lens dry open, but with caps on, in a dry, not hot place; the bag and rain cover need air too. Even weather-sealed bodies are not waterproof but only protected against splashes. How to spot sensibly on wet days at all is shown in the guide Plane spotting in bad weather.

After cold: avoiding condensation

The critical moment does not come outside but when you go in. Cold gear in warm, humid air fogs up immediately – on the outside and, in the worst case, inside. So while still in the cold, put the camera and lens in the closed bag or a sealable pouch and let them slowly come up to room temperature indoors. Take out the memory card and battery beforehand so that you do not have to open the bag. More tips for the cold season are in the article Plane spotting in winter.

After dusty days

Dirt tracks, dry meadows and gravel areas bring fine dust into every seam. Blow out the body, dials and zoom rings with the blower, wipe the body with a slightly damp cloth and shake out the bag. With zoom lenses with an extending barrel, it is worth wiping the barrel before retracting it – otherwise it pulls the dust inside.

Avoiding dust is better than cleaning

The best sensor cleaning is the one you do not have to do.

• Lens changes with a plan. Switch the camera off, hold the mount facing down, back to the wind, change quickly. If you arrive by car, change inside the vehicle rather than at the open fence.
• Caps on immediately. The body cap and rear cap belong within reach in a fixed pocket, not loose in the jacket.
• Two cameras instead of switching. Many spotters work with two bodies – telephoto on one, a shorter focal length on the other. That saves not only time when the rare jet unexpectedly arrives early but also lens changes. Which bodies are suitable is shown in the overview The best camera for plane spotting.
• Keep the bag clean. Crumbs and sand in the inner lining end up in the mount sooner or later. A camera backpack with fixed compartments helps; ideas are in the article Camera backpacks and bags for long telephoto lenses.

By the way, if you are buying used, you should check the sensor condition right at the viewing – with exactly the dust test above. More on this in the guide Buying a used camera and lenses.

The care kit for your spotting bag

You do not need a big lab. A small, clean kit covers almost everything:

• Large blower without a brush – for sensor, lenses and body
• Soft lens brush – for the front element and body seams, never for the sensor
• Two microfiber cloths in a sealable pouch – one for glass, one for the body
• Lens cleaner and lens tissue – for fingerprints and streaks
• Absorbent cloth or small towel – against rain and spray
• Rain cover for camera and lens – for showers in the open field
• Sealable pouches – against condensation after cold days
• For home: sensor swabs of the right width and sensor cleaning fluid

What else belongs in the bag is shown in the gear checklist for plane spotting. For airshows with long days on dusty meadows, there is also the checklist for airshow day.

What to watch for

• Never clean the sensor at the spot. Wind, dust and time pressure are the worst conditions for it. At the fence, at most the front element gets cleaned.
• No household cleaner, no eyeglass cloth with an unknown coating. Only products intended for camera optics.
• Be careful with warranty. Check your manufacturer’s terms before you wet-clean yourself.
• Retouching is no shame. A single spot can often be retouched away faster than a risky cleaning just before a tour takes. The guide Editing aircraft photos offers tips.
• No brute force. Stubborn dirt, fogging inside the lens or water in the body belong in the workshop.

Conclusion

Camera care for spotters is less technique than habit: test regularly, remove dust with the blower instead of force, make lens changes consciously and invest a few minutes in your gear after rainy or cold days. The airport environment is rough but predictable – if you know it, you rarely have spots in the sky. And if one does remain, service is the safer choice than a second, hurried cleaning attempt.