Cleaning Your DSLR Sensor
A guide on how to get rid of sensor dust at home
By K David in Tutorial Videos on Jun 12, 2014
We all paid a lot of money for our digital single-lens reflex (DSLR) camera bodies. So dust on an image can be a disappointment. Sensor dust, unlike lens dust, necessarily leads to image quality loss, unsightly image spots, and added work in post. So, here's a process for dry-cleaning your DSLR sensor. Simply searching for sensor cleaning returns a dozen different ways, tips, and theories on what and how to do it. This method presents DSLR owners with low-risk, inexpensive sensor cleaning. Of course, clean your sensor at your own risk.
For those of you who would like to see this performed before trying it yourself, here is a video of me demonstrating the practice on my Pentax K-7.
For this procedure, you'll need this equipment:
- Fully charged battery
- Rocket-type air blower
- Static brush
- Lint-free cleaning swabs -- preferably disposable
- Cotton swabs
- New, powder-free latex or nitrile gloves
Here is some optional equipment:
- A lighted loupe or a loupe and a flashlight
Also, you'll want to avoid these items:
- Compressed air dusters
- Rubbing alcohol, WD-40, acetone, and other liquids and solvents
- A dusty or dirty environment
- Giottos AA1900 Rocket Air Blaster Large
- D-SLR Sensor Cleaning Brush for 1.5x & 1.6x Sensors
- Digital Survival Kit - Sensor Swab Type 2
Not all cameras have a dust removal function built into them. If your camera does have an ultrasonic dust removal feature, make sure you turn it on and if the option exists to make it a start-up feature, you should do that, too (current Pentax cameras, including the K-500, K-50, K-5, and K-3 all feature dust removal).
Begin this process by taking a dust reference photo. The reference photo will help you target dust if needed and also help you determine when your sensor is clean. If you have a pinhole lens, use that. This video shows how to make a quick and inexpensive pinhole lens.
If you don't have a pinhole lens, that's okay. Simply use a normal or slightly wide lens (50mm to 28mm, in 35mm terms) stopped down to f22. Your reference photo should either be a clean wall free of decorations or, ideally, a cloudless daytime sky. This video shows you how to determine if your sensor has dust using a pinhole lens and a light bulb.
The first step will be cleaning the reflex mirror and focusing screen. Using a dry cotton swab, gently touch the tip of the swab to visible dirt on the mirror and focusing screen. This will help make the image in the viewfinder clearer and remove distractions caused by large dust particles.
To clean your DSLR's image sensor, you'll first need a fully charged battery or your DSLR will not allow you to use the mirror lock-up (MLU) feature for sensor cleaning. With your fresh battery inserted, find the sensor cleaning item on your menu. The location will be different for each camera model. Lock the mirror up.
With the mirror up, the first step is to hold your DSLR with the sensor facing the ground. Using your rocket blower, blow air into the sensor housing. First blast the rocket blower into space a few times to remove any dust that may have settled in the nozzle. Then blow air onto the sensor.
At this point you can turn your camera off (most cameras have to be turned off to end sensor cleaning MLU.) Make sure that none of your equipment is in the mirror box when the camera is turned off because the mirror will snap back to its resting position.
Take another reference photo. Compare the photo to the original and see if dust remains in the image. If so, you will need to proceed to the next step. If not, then you've cleaned your sensor easily and can go back to taking photos.
If you have the lighted loupe or a loupe and flashlight, those can help identify dust locations. Remember as you clean that the image on the sensor is upside-down and reversed, so if dust is in the upper right corner of your image then it's actually on the lower left of the sensor.
After re-activating your cameras MLU, start the nest step by using your electrostatic brush. Use the rocket blower to blow air through it to charge it with static. This also helps remove any dust that was stuck in the brush after the previous sensor cleaning. Lightly run the brush's tip over the sensor; the idea here being that static will attract the dust. Forcible contact can risk the brush ferule contacting and scratching the sensor or a brush hair becoming caught in part of the sensor or shutter mechanism. Taking another reference photo at this point is optional.
Using a lint-free cleaning swab, you'll want to clean the sensor. Pass the swab over the sensor once in each direction -- left to right over the whole sensor followed by up and down. Avoid contacting the edges of the sensor housing as this can cause oils to be taken up by the cleaning swab and transferred onto your sensor.
At this point, remove your tools from the shutter box and turn your camera off. Take another reference photo. If the photo looks good to you, then you're done. If the photo still shows an unacceptable number of dust spots, then repeat the process beginning with the air blower.
To make sure that you have the best sensor cleaning experience you can, avoid using compressed or canned air in lieu of a rocket-type blower. The canned air is actually tetrafluorocyclene or a similar compound and can spray frost from the can. This will almost certainly damage your sensor. Even without frost, the velocity of gasses escaping from canned air can damage your sensor. Also, avoid using a vacuum, even the small ones suited for cleaning keyboards. Those can cause the sensor to move in ways it should not or beyond the tolerances of the internal shake reduction system (if your camera has an internal system.) Also avoid sticking your fingers into the shutter box or directly touching the sensor. Removing finger grease from the sensor is a difficult proposition.
Another thing to be sure of is that you don't accidentally bump the off switch while cleaning the sensor. That will cause the shutter to close and reflex mirror to snap back into place, which can cause significant damage to your camera.