What is dust to your camera

A common problem of most photographers is the dust, be it in or on the lens, as well as on the sensor.

Considering it is annoying for the most camera owners, let us first see how important it really is and how much time and effort should we invest into cleaning and keeping our lens free of dust.

The dust ON the lens

Dust on the lens is the most frequent problem. The best way to remove it is with a tool made for the job. If the lens is dirty clean it with some lens wipes very gently and then put a UV filter on and leave it on. If the images are fine don’t mess with the camera.

It is not recommended to use the compressed air cans you use on computers. They are too powerful, and you might run the risk of scratching the lens if you happen to have a tiny piece of something hard on or near the lens surface.

The dust IN the lens

If the dust is inside the lens, then we can speak of a more serious problem. Canon lenses (except for a select number of the L series lenses) are not dust or weather sealed. So each time you work the zoom mechanism on an inexpensive lens, the mechanism is working like a giant billow allowing air (and dust and moisture) to flow through the lens and camera body. Sometimes large dust particles can accumulate on the different lens elements, but it does not have any impact on the quality of the photo.
The dust particles inside the lens are PRETTY FAR from plane of focus and as they are VERY near to chip/film plane, they are always safely far from DOF.

The dust on the sensor

If the dust is on the sensor, the best way to clean it is to use a product like discofilm. Using any other method other than using discofilm or a sensor film product does nothing but pushes dirt around the sensor without lifting from the sensor surface. If the camera is turned on while changing lens, the sensor is charged and it might attract dust. A CMOS sensor does not attract dust, whether the camera is on or off but a CCD sensor does.

The cause of dust gathering

It’s mainly a problem of zoom lenses, because when you zoom at the long end, then there is usually an open hole through which the dust can go from the camera to the lens. You can see it when you unmount the lens. Zooms tend to be worse than primes, as the air displacement of the lens elements’ zooming action sucks in dust.

It is considered that push-pull zooms are worst of all. This is also a problem on trips, where there is a lot of dust and you need to change frequently lens while being outdoor. Also the home storage seems to be important.

The detriment of dust

Take a couple of test shots to be sure, but I will not worry about it at all. Point the camera at a bright white wall. Focus at minimum distance (regardless of where the wall is). Do you see the dust or any effect of it? Then try a dark wall. When dust is right in the middle of the glass, it makes a lightly fuzzy impression on the print. Being inside the lens, they are not “in focus” so they can’t be seen in the viewfinder or on a print. If there was a lot of dust, haze, etc. on lens elements it would start to degrade your image, though.

Generally speaking the dust will be uniformly spread all over the photo and will not be visible on the photo as long as it is also far from the film/chip plane. But that’s always true because there is always a space for mirror between the rear lens element and the sensor/film plane. So all the damage to a photo the dust can do is to reduce the light that falls on the sensor.
If you have dust on the sensor, then you can get some dark areas on your final pictures. It also depends on the angle of the light that falls on the lens, as it can reveal the dust particles or not, on the final shot.

Preventing dust from getting to your lens

Using a filter will help prolong the life of your lens. It is the most common and efficient method to save your lens from damage. Another advise would be using high-quality scotch tape to cover your lens. Although some say they tend to leave something behind almost always. It is true that the amount of glue left will be extremely small in these cases, but still it could then hold to more dust than the lens would have acquired otherwise.

A relatively large and completely clear plastic bag could save your camera from dust. Put the camera in the bag, facing down and change the lens with the camera in the bag. It is especially useful in dusty, outdoor shootings.

Cleaning the dust

To remove dust and lint, a simple microfiber lens cloth will solve the problem. Use light strokes working towards the outside of the lens. For mud or other stubborn dirt, you will need to use a cleaning solution designed for photographic lenses. If you use ammonia or another household cleaning solution you could permanently damage the lens. Most photographic lenses have a fine coat of oil on their surfaces. Eventually, this coating will wear off with repeated cleanings of any kind.

You can do sensor cleaning at home, using the special tools for this. Basically speaking you’ll need three items: a sensor brush, some cleaning solution(like Eclipse) and eventually a sensor loupe.

You can also read some good toturials on sensor dust cleaning from cleaningdigitalcameras.com and impulseadventure.com. Below you have a demonstration about how it is done. You can see it’s a simple procedure and you have nothing to worry about.

The general conclusion would be that every camera has dust in it and this is not really a reason of concern as the methods of cleaning in most cases are pretty simple.

You don’t actually need to be in panic every time you see some lint on the camera, because it is not of so much damage to your shots. Just be sure not to miss a shot because of this