(April 2014 update: Recently I had the opportunity to try a new sensor cleaning product, the Sensor Gel Stick. Based on my initial experience this seems like a more effective and faster way to clean sensors that any of the methods mentioned below—though I must point out that my experience with the product at the time of this writing is still limited. The product (available here, at least if it isn’t out of stock) is a cube of a sticky gel material attached to the end of a plastic “wand.” The gel cube is placed in contact with the surface of sensor’s glass cover, and the dust adheres to it. Since the cube is smaller than the sensor, this process is repeated across the sensor surface. I have to reposition the gel cube about 8 times to cover the surface of a full frame sensor, a process that takes less than a minute and which can easily be done while traveling. To remove collected dust from the gel cube you press it against a supplied sheet of “sticky paper,” which has a surface that is stickier than the gel. I tried this system partially out of desperation, as my aging Canon 5DII had picked up a ridiculous number of dust specks that were resistant to other methods of cleaning. After the first cleaning there were no noticeable spots left on the sensor. I continued to use it during a four-day shoot in Death Valley, a location known for dust—and, again, the result was impressive. The product is not cheap, costing about $50 for the gel stick and the sticky papers. Frankly, I think it is overpriced—but because it works so well I was willing to pay the price. I have recently seen similar products online from other distributors at lower prices, though I cannot vouch for their quality.)
When I got my first DSLR I was very upset if I got any dust in a shot. I was also very paranoid about cleaning the sensor*, having read too many posts about how one can damage the sensor during cleaning. Now that I’ve used DSLRs quite some time I’ve gotten over it and life is much, much easier.
Here is a summary of my approach** to dealing with sensor junk…
Rule #1: Modern cameras typically include dust-reduction systems that rely on vibrating the sensor to dislodge dust particles. I set mine to operate automatically each time the camera is turned on or off. In addition to ensuring that the process runs regularly, this automatically runs it after every lens change, the time when you are most likely to pick up dust. Cameras also allow you to manually trigger a dust-reduction system cycle from the control menus, and I do this if I notice a dust spot while shooting. (If you have ever shot for a day or a few days without checking, only to realize that you had picked up a big dust bunny on day one and that it appears in all of your several hundred or more photographs, you will adopt this practice!)
Rule #2: I don’t worry too much about a small amount of dust in your captures. I rarely can get a sensor clean enough to get perfect, dust-free shots at smaller apertures, and when I do the dust will soon return. Rather than worry too much I’ve found that it is easy to quickly fix most small spots in post-processing. Using one or the other tool, I can usually deal with most dust spots in a matter of a few seconds in Adobe Camera Raw (ACR) or Photoshop. (My preference is to do this in ACR during the raw conversion process. This fits better with my workflow which relies on the use of smart layers in Photoshop.)
Rule #3: When the dust gets to the point that dealing with it in post is no longer efficient, I try the easiest thing first. When I notice a larger than usual speck or when the build-up gets to the point that post-processing cleanup is either taking too long or not working right, I use a blower to try to clean out the worst of the stuff. More often than not this is enough and I can go back to relying on rule #2. Point the tip of a good blower bulb into the chamber but keep the tip itself just outside. As you blow a few dozen puffs into the chamber and toward the sensor, change the angle of the bulb to ensure that you get full coverage. It is probably best to hold the camera with the open chamber facing down. (Don’t overdo it, since the blower can move some dust onto the focus screen of some cameras, leaving annoying bits of dust that do no real harm and will not affect your photographs but which are very difficult to remove.) Update: Given the ease of use of the sensor gel stick product described in my note above… while I might still try a blower, if that didn’t work I would move on to the gel stick right away. In addition, I doubt that I will have much use for the sensor brush described below, and I expect that wet cleanings will now become an extraordinarily rare event.)
Rule #4: Sometimes rules #1-#3 aren’t enough. At this point I try a static charged sensor brush, being very careful to avoid letting the brush touch anything but the sensor* glass itself. Yes, the brush can pick up other stuff in the chamber, and I have learned from experience to avoid this. However, most often the brush is all I need to use to get my sensor back to “sufficiently clean” status. With care and a bit of luck the brush method can sometimes get the sensor absolutely clean. The whole task takes me just a minute or two. I rarely have to escalate past the “blower and brush” technique – probably not more than once or twice a year – and in nearly all cases I can get the sensor glass very clean this way.
Rule #5: On rare occasions rule #4 fails, too. If the contamination is adhering too firmly to the sensor surface I resort to wet cleaning with Eclipse fluid and PecPads. I can rarely get it right in one attempt, so I plan on having to work at this a bit. Be very cautious to not use pressure or “scrub” the sensor glass. Let the fluid loosen and/or dissolve the material and gently wipe it off with the pad attached to the “spatula” tool. Read the instructions for this cleaning method very carefully before attempting it. It isn’t terribly difficult but there are a few ways you could go wrong including: pressing too hard and damaging the coating on the sensor glass, transferring lubricants to the sensor from other parts of the camera chamber, leaving streaks on the sensor. Eventually I get a reasonably clean sensor with no streaks.
Rule #6: On very rare occasions a combination of methods is required. Often the wet cleaning works well for me but leaves a few spots of dust on the sensor. For this reason I frequently follow the wet cleaning with a quick once-over with the static charged brush.
From all of this, it might sound like I’m sensor-obsessed. I’m not. Remember rule #1 is the one I follow most. I usually go many months between real sensor cleaning sessions.
Update #1: Since I the time when I originally wrote this, I acquired a Canon EOS 5D2 body which includes an automatic dust reduction system that vibrates the sensor when the camera is turned on and off, thereby dislodging dust from the sensor (AA glass) on a regular basis. After using it since late 2008, I find that the “dust shaker” system on this camera is very effective. I rarely need to do a manual sensor cleaning – although I used to do this more or less monthly with my previous Canon 5D. When a dust speck does show up occasionally, it usually disappears a few frames later after I switch the camera off/on. If this doesn’t do it, sometimes manually running a cleaning cycle in the camera will resolve the problem. I have only had to resort to a wet cleaning once since I acquired the camera.
Update #2: I often read that some people take their cameras to the shop or send them to the manufacturer for sensor cleaning. Some apparently even take their cameras in for sensor cleaning on a regular schedule, perhaps as often as every month. I’m not sure if this comes from being over-cautious about potential sensor damage, aspiring to a “perfectly clean” sensor, not wanting to spend the time on the process, or something else. Except in extraordinary situations, I don’t think this is necessary or a good idea. In my opinion, it is not necessary to fear the sensor cleaning operation as long as you are reasonably careful. Once you do it a few times it becomes quite quick and easy. Taking your camera to the shop or sending it to the repair facility is going to cost you a significant sum, take considerable time, and probably not result in a cleaner sensor in the end.
Update #3: Regarding Update #2 above, a message from another photographer has made me soften my “don’t have the shop clean the sensor” position, at least in some cases. One photographer pointed out that he has a service plan that includes six free sensor cleanings per year. A few years ago, I would have counseled against relying on this – since early cameras without sensor cleaning systems often needed to be cleaned frequently and on short notice. However, the newer cameras rarely need a serious sensor cleaning – and in this case I can see how simply sending the darn thing in (while you keep shooting with your backup camera) could make sense for some people. (I still feel that you should be able to clean the thing in the field if necessary.)
Update #4: The availability of the gel stick tool (described near the start of this post) has changed things quite a bit. None of the older methods were as easy and effective, so back then I often tried to avoid moving to the more invasive and time-consuming sensor cleaning methods until I had no choice. Since cleaning with the gel stick is both fast and effective, I tend to move through the earlier approaches much more quickly and may even skip over them. For example, it is hard for me to imagine many situations other than oily residue on the sensor that would lead me to do a traditional wet cleaning at this point.
- I’ll anticipate that someone might feel obligated to write, “You aren’t really cleaning the SENSOR! You are cleaning the glass cover over the sensor, you nitwit!” Yes, I know that. It is just easier to refer to the whole assembly as “the sensor.” :-)
** Disclaimer: This report describes what I do, but I am not any sort of certified expert on these things – as I wrote, this is “my approach.” I strongly urge you to seek out and learn from other official sources of information on sensor cleaning and related issues. The inside of your camera contains fragile and sensitive electronic and mechanical components and it is possible to cause damage while working there. You should read and carefully consider warnings from the manufacturer of your camera and any accessories and tools you use on it. If you are not convinced that you are competent to do this work on your camera, you can always take it to a professional. I do not claim that my methods are the best or most appropriate, nor that they meet the standards of the manufacturers of the camera equipment nor do I recommend that you use my methods in place of manufacturers’ official recommendations.
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(Most recent update: July, 2014)
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G Dan Mitchell is a California photographer and visual opportunist whose subjects include the Pacific coast, redwood forests, central California oak/grasslands, the Sierra Nevada, California deserts, urban landscapes, night photography, and more.
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