Frequently Asked Questions
Why does the sensor in my Digital SLR get dirty?
Dust is everywhere in the environment. The removable lens on a DSLR allows dust to enter the camera body where it will eventually find its way onto the imaging sensor. When you consider that the average pixel on the sensor is around 7 microns across (.007mm) it doesn’t take a large speck of dust to cover several pixels and cause a visible blemish on your images.
I have never taken the lens off the camera, yet I can still see spots on my images, why is this?
A modern DSLR is a complicated electro-mechanical device. With many moving parts both within the camera body and the lens, simple wear and tear can cause minute particles of dust within the camera. Dust can also enter the camera body through the memory card door or through small gaps in the body panels. Professional grade cameras usually feature extra seals within the body to minimize dust and moisture entry.
I had my camera professionally cleaned but when it came back the sensor was still dirty, should I complain?
While a professional clean should leave the sensor much cleaner, its not unusual for the odd speck of dust within the camera body to find its way onto the sensor while the camera is in transit back to the owner. If you take a test image before sending the camera away, and another when it is returned, you will be able evaluate the effectiveness of the cleaning service. Expecting the sensor to come back 100% clean is unrealistic.
How easy is it to clean the sensor myself?
We think it is quite easy to clean the sensor. But as the sensor is the most expensive component within the camera it should be cleaned extremely carefully, using the right cleaning tools. There is a lot of information (and mis-information) available on the subject of sensor cleaning. You may find the tutorials on this site helpful, but it is worth doing some research on the subject first. Then practice on an old filter or small mirror so that you are comfortable using your cleaning tools before cleaning the sensor.
What is the best product to use for sensor cleaning?
There is a wide range of sensor cleaning products available today. While some work much more effectively than others, there is no ‘magic wand’ available. Each different method has it advantages and disadvantages. You may find the ‘sensor cleaning methods’ article on our help pages useful. A key principle is the need to clean loose dust particles and ‘stuck-on’ marks using different techniques.
How often should I clean the sensor?
There is no correct answer to this question. A studio-based photographer will need to clean very rarely, while a motor sports photographer may need to clean weekly. It really depends on the environment in which the camera is used, how many lens changes are made, how much care is used when lenses are changed, how clean is the camera body externally and so on. Cleaning the sensor every time a new ‘spot’ appears on the image, will be a frustrating experience, as well as expensive in terms of cleaning materials. Equally frustrating will be retouching fifty blobs from each and every one of 400 wedding photographs. Our advice is to leave the odd blemish alone until the number visible reaches your own tolerance level, at which point give the sensor a clean. Your tolerance level may vary depending on the importance of your upcoming photography tasks.
I have used a blower to clean the sensor, but I can still see spots, why is this?
While a blower can blow loose dust particles off the sensor, sticky marks will not come away with a simple blow. These ‘welded-on’ marks will need to be removed using some type of wet cleaning system. I.e. using a cleaning swab and fluid. There are numerous wet cleaning systems available today. Our recommendation is ensure you do not use a water based cleaning fluid as these tend to leave drying marks. Ensure that all loose dust particles are removed from the sensor before using any swab.
How do sticky marks get onto the sensor?
There are numerous causes for dust to become stuck-on and hence stubborn to remove from the sensor. Most household dust originates from discarded skin cells and these dust particles can be greasy. Some new cameras can mist microscopic droplets of lubricant from the shutter and mirror mechanisms onto the sensor. Pollen is sticky and diesel particulates can also contaminate the sensor. If the camera gets cold and is brought into a warm room moisture can form ( for example, when the lens steams up) wetting dust particles and causing them to stick to the sensor surface.
I have cleaned the sensor but can still see spots when I look through the viewfinder, why is this?
The viewfinder and the sensor are not the same! If you remove the lens from the camera, you can see a small mirror. This reflects the image from the lens up onto the focusing screen above. If you can see dirt in the viewfinder, then it is most likely the focusing screen that is dirty. When you take a photograph, the mirror swings up, the shutter opens and the image is exposed onto the sensor. Follow this simple rule If you can see marks on the image on the computer screen (or the rear LCD on the camera), then the sensor is dirty. If you see marks in the viewfinder, then the focusing screen is dirty. Be careful when cleaning the focusing screen or mirror, both are very delicate. Please call for advice.
How can I stop my sensor getting dirty?
In general, you cant! Unfortunately dust is fact of life and the atmosphere is rarely free of dust particles. You can minimize dust contamination by changing lens carefully; hold the camera down when the lens is off. If you are outside, keep your back to the wind when changing lenses. Keep the camera body clean; keep your lenses clean. These ‘hygiene’ steps will reduce sensor contamination. Remember, the key strength of the DSLR is the ability to change lenses. This makes the DSLR extremely versatile; don’t let dust spoil your enjoyment of DSLR photography, dust is an easily managed problem.
Can you clean my camera sensor please?
Yes! Please click here for more information.