New Tutorial: Camera Sensor Cleaning

[McQ]

This article isn't yet public on the main site, but I thought I'd release it here first. It's a topic that any SLR user will likely need to investigate at some point:

Tutorial: Digital Camera Sensor Cleaning

This article covers how to identify sensor dust, the pros/cons of available cleaning methods, general cleaning technique and best practices for minimizing sensor dust accumulation, amongst other topics.

As usual, please let me know if you feel anything is unclear, if you notice any typos or just want to add something from your own experience.

Many thanks!

[Colin Southern]

Hi Sean,

Just a couple of things came to mind ...

1. Of course, we're not cleaning the sensor, but the filter over the sensor -- worth mentioning this? Also - because of this - it's been my experience that sensors are almost impossible to damage (unless you really try hard!).

2. Another couple of products which I use ...

1. The "sensor stamp". It's basically a silicon surface with low-grade adhesion that you "stamp" on the sensor. Dust sticks to the device (which is then removed by sticking the device against a supplied even stronger grade adhesive surface). Works well.

2. The sensor pen (good for removing silicon grease a-la below!).

The biggest issue I have with sensor brushes is the face that I ALWAYS seem to get a few hairs over the area surrounding the sensor, which ALWAYS seems to have silicon grease on it ... which inturn smears onto the sensor (excess lubricating silicon flying around is a known issue with the 1Ds3 / 1D3 - my mirror is covered in it).

[jiro]

Very nice. I think you did it quite well. Thank you very much, Sean. I'm pretty sure all the members and even the visitors will benefit a lot from this tutorial.

[McQ]

1. Of course, we're not cleaning the sensor, but the filter over the sensor -- worth mentioning this? Also - because of this - it's been my experience that sensors are almost impossible to damage (unless you really try hard!).

Yes, this fact does imply a lower risk of sensor cleaning, but a scratched sensor filter would still impact the image, and would require the camera to be sent back into the manufacturer (which could be quite costly if the model is outside its warranty). I will add something on this in the intro section where I show the sensor/filter diagram and talk about all the layers in front of the photosites.

1. The "sensor stamp". It's basically a silicon surface with low-grade adhesion that you "stamp" on the sensor. Dust sticks to the device (which is then removed by sticking the device against a supplied even stronger grade adhesive surface). Works well.

2. The sensor pen (good for removing silicon grease a-la below!).

The biggest issue I have with sensor brushes is the face that I ALWAYS seem to get a few hairs over the area surrounding the sensor, which ALWAYS seems to have silicon grease on it ... which inturn smears onto the sensor (excess lubricating silicon flying around is a known issue with the 1Ds3 / 1D3 - my mirror is covered in it).

Thanks for sharing these -- they're interesting options. There's definitely a dizzying array of cleaning tools out there now. I'll have to admit that I was initially hesitant to use these types of devices due to concern over leaving a residue from an adhesive (either from the device itself or indirectly from the device cleaner). However, this fortunately doesn't appear to be a problem since the device itself seems to work because the (slightly) deformable silicone is more likely to mold around the dust particle (and hold onto it) than the more rigid sensor (filter) surface. It also doesn't drag across the surface, so there's little to no risk of scratching anything. What's also encouraging is that Canon has sold these themselves as official cleaning kits (but only in certain countries...so far). I'd just want to keep this device *incredibly* clean...

[Peter Ryan]

This topic is well worth covering and I am sure this will help members and guests. Well done Sean.

[inkista]

I actually disagree about the blower being relatively useless. It actually works pretty well for me, as most of my dust is dry, not the welded-onto-the-filter-while-damp variety. But I would suggest that perhaps you should describe how to use a bulb blower properly: i.e., with the camera facing downwards, and giving enough time for the dust to drift down and out of the camera body. If you just blast the blower into the camera body while it's upright or (worse) face-up on a table, then, yeah, you're just shoving dust around.

Also, just for contrast, here's the lensrentals tutorial on sensor cleaning. It includes the stamp and sensor pen methods, so you can see them in action.

[McQ]

I actually disagree about the blower being relatively useless. It actually works pretty well for me, as most of my dust is dry, not the welded-onto-the-filter-while-damp variety. But I would suggest that perhaps you should describe how to use a bulb blower properly: i.e., with the camera facing downwards, and giving enough time for the dust to drift down and out of the camera body. If you just blast the blower into the camera body while it's upright or (worse) face-up on a table, then, yeah, you're just shoving dust around.

Thanks for the feedback, Kathy. This is true -- the blower works just fine for lot of people (as part of a multi-tool strategy, or with really dry and loosely sitting dust). Something that I didn't mention (but perhaps should have) is that blowing dust within the camera body (but not necessarily on the sensor) can also be an advantage, since much of this could one day end up on the sensor itself. It's all about technique though, so I'm glad you came to the blower's defense -- and perhaps I was a bit too harsh on this method . I'll add this to the list of tutorial updates that will be included in a couple of days. Most of the other tools are still much more powerful and effective, but the blower does deserve its rightful place in the cleaning workflow.

[PopsPhotos]

Nikon calls it "mirror lockup," which it is not. It is to raise the mirror for cleaning.

Here is another tutoring site for cleaning.

http://www.cleaningdigitalcameras.com/

Pops

[Klickit]

Great tute to add the current arsenal, Sean. I was super-nervous the first time I cleaned mine and will possibly be just the same the next time.

But - as the grammar police, I have to point this out: "(look closely -- there's at least eight)."
Should be "(look closely -- there are at least eight.)"

[Colin Southern]

Most of the other tools are still much more powerful and effective, but the blower does deserve its rightful place in the cleaning workflow.

The problem I have with the blower is that it's never 100% effective ... which means I then need to go in with one of the other options afterwards anyway

Perhaps another thing worth mentioning is that it's always a good idea to give the camera body a wipe down with a damp cloth before doing any sensor cleaning, paying particular attention to lens mounts (on both camera and lens) (the dirt that's there today will be the dirt that's on the sensor tomorrow).

[PopsPhotos]

Using the blower first, camera down and waiting for the dust to drift out, is to get as much grit out of the way before you put anything in to touch the sensor cover.

Pops

[McQ]

Of course, we're not cleaning the sensor, but the filter over the sensor -- worth mentioning this? Also - because of this - it's been my experience that sensors are almost impossible to damage (unless you really try hard!).

OK, I've now added a note near the start of the "sensor cleaning methods" section (where I talk about the risks involved in cleaning). This reads as follows:

*strictly speaking, only the outermost layer of filters is what actually gets cleaned -- not the camera sensor itself. This is good, because replacing this filter is much less expensive than a new sensor (it can usually be repaired by the manufacturer if you send your camera back).

I also added a note about wiping down the camera body and lens mounts in the "prepare" section of the general cleaning steps.

[McQ]

I actually disagree about the blower being relatively useless. It actually works pretty well for me, as most of my dust is dry, not the welded-onto-the-filter-while-damp variety. But I would suggest that perhaps you should describe how to use a bulb blower properly: i.e., with the camera facing downwards, and giving enough time for the dust to drift down and out of the camera body. If you just blast the blower into the camera body while it's upright or (worse) face-up on a table, then, yeah, you're just shoving dust around.

I've now overhauled how I describe the blower throughout the article, in addition to adding a specific "how to" for this tool in the "How to Clean Your Sensor: General Steps" section. This ought to address your points. Let me know what you think.

[Jim Bell]

Older digital cameras did not have the chip cleaning ability. I used to set the camera on "B" and held the shutter open until I had brushed off the sensor with a camel hair brush. To avoid static I would gently breath on to the brush and very carefully sweep across the sensor. It always worked. I would not recommend an air blower - too fierce. If you are using Photoshop CS5 the problem of sensor spots is not such as problem because you can always use the spot healing with content aware.

[mythlady]

Very well done, Sean -- I only found one little glitch, a missing word in this sentence:

Gently place the tissue-covered of your tool on the edge of the sensor and follow the motion shown in the diagram above.

Now if I can just get up the courage to do my old Rebel -- I was going to pay $40 to have it done, but maybe I'll try it . . .

[rick55]

Hi, Sean;

This is a wonderful tutotial. What I like most are the good descriptions of the sources of problems. Cleaning the sensor because of a spot on a lens is certainly something to avoid.

In the opening paragraph, there's a little bit of a non sequitur. It begins, "..., you'll eventually encounter spots in your photos...." But then the second sentence says, "... or is instead the result of a dirty viewfinder...," which of course won't cause spots on photos.

Along the same lines, for diagnosing the source of a spot, if you can see it through the viewfinder, you can take a picture with the spot on a landmark, like the upper-left panel of a door. If it isn't on the image, it's on the viewfinder or mirror. If it is on the image, it's on the lens (for a DSLR, at least).

Under "Sensor Cleaning Methods," in the first paragraph, maybe not use "alternatively" to start the last sentence. The risk of direct contact to the sensor isn't alternative: both can happen.

All in all, very useful, and very clear and sharp, as always.

Cheers,
Rick

[Steve S]

Very good tutorial sean. A good way to check for dust...............start up your editing program and fill a layer with sky blue. Turn your lens to manual focus. (focusing isn't necessary) Turn your aperature to f/22 or higher. Take a photo of the screen, holding the lens a few inches away. Move the lens in a circular motion as the photo is exposing (long f/stop will take a couple seconds.). Upload your photo and you will see the dust spots . Don't forget they are inverted on the sensor.

[grayowl]

I agree, this is a very good tutorial. A very important sentence in it is: "an ounce of prevention is worth a pound of cure".

Most of the dust come to the sensor through the bayonet opening when you are changing lenses. If your camera is not the cheapest one and it is well sealed, not the majority but all particles have to pass the bayonet. Their first stop is the space behind the lens but in front of the SLR-mirror. They stay here a while before they look for a seat on your sensor. Therefore, a very efficient practice how to keep the sensor clean is to keep the space in front of the mirror free of dust. In contrast to the dust sitting on the sensor, the dust on the black surfaces in front of the SLR-mirror is often visible to the naked eye.

The more often you use your sensor blower to clean this space, the less often you have to use it to remove the dust from the sensor.

Also important: you have to blow the space in front of the SLR-mirror free of dust before you start the sensor cleaning procedure, i.e. before you press the shutter for getting the open access to the camera's sensor.

I'm sorry for my bad English, I hope, my images are better than my English.
[Nikon D200 with 12-420 mm and Canon PowerShot S90 for underwater photography]

[pwnage101]

What a coincidence, I was trying to describe to a friend how dust affects an image so I rendered this diagram (using Blender3D):


For now on I'll just use your tutorial

[Glenn NK]

As for damaging a sensor, I didn't really try very hard.

The filter on my 30D is not the original - the original is lying on my desk as a reminder that despite being careful, things can happen.

Glenn