The following is information from Cooper Hill images and put together by them.
Cooper Hill Images sells the products described in this tutorial
Disclaimer: The following information is to be used at your own risk. AlphaMaxxum cannot be held responsible for your actions that might result in any damage to your sensor. If you are not sure, have your sensor cleaned by a professional.
Introduction
Welcome to the home of the "Copperhill" sensor cleaning method. We hope you learn a few things in this tutorial and have a little fun in the process. Once you get a grasp of the basics, please browse through our store where we offer only the BEST sensor cleaning products available.
FAQ: Why should I worry about dust on my sensor?
1) A heavy buildup of dust will cause a loss of contrast in your images and will show up as spots in your light backgrounds.
2) If you shoot landscapes, macro or portraits, dust will appear in your photos, even stopped down to f/5.
3) Time & money - sending your camera in to the manufacturer every time dust builds up to a major degree will find you without your camera for 5 to 10 days at a time and will cost anywhere from $35 to $75 for each cleaning. A $29 cleaning kit should last you at least 4 years.
NOTE: Chuck Westfall of Canon USA has made this point on numerous forums and has recommended this Copper Hill tutorial and products as one of several effective solutions in the marketplace.
4) The dust-shakers in the latest D-SLRs are a hit-or-miss proposition, some units seem to work a little better than others. Most of them can move the loose specks around but all of them are totally useless against chamber lubricant.
5) CHAMBER LUBRICANT - the new bane of D-SLRs. Manufacturers are using more and more lightweight oil on the moving parts such as the mirror hinges and shutter blades, and when you take a shot, it sometimes gets splattered on your sensor's surface. And once you have a buildup of this lubricant, it only follows that loose dust specks will be cemented into this goo. In the olden days of sensor cleaning, people guessed that super-stuck dust specks occured when moisture latched onto loose dust particles and then settled on the sensor. But a few years ago, individual oil spots began to show up in images, this was the first clue. The final proof of chamber lube's horrible sensor contamination came when people used a sensor brush and actually smeared the oil across the surface. We now had not just a dust problem, it was a dust AND lubricant problem.
# 1 The "Copperhill" Method
If you are reading this now, you probably know that an imaging sensor is a fabulous dust magnet which needs to be cleaned regularly. These filters (anti-aliasing or low pass on a CCD, IR dichroic on a CMOS) are mounted on top of the actual sensor chip with a small gap of airspace between the two. When people refer to "sensor" cleaning or swabbing, it is these filters that will be wiped with a swab, and not the actual CCD or CMOS. Other than making your light background images look like a case of chicken pox, a moderate to severe accumulation of dust particles will cause a noticeable loss of contrast in your images. That's why keeping your sensor dust-free is so critical and necessary to D-SLR photography.
There are two kinds of dust particles you'll have to deal with: loose specks that will just move around on the sensor, and "super-stuck" particles, which have the same characteristics as dried-up bug-splat on a car windshield. There are many theories as to how they become this way (the dust specks, not the bugs), including internal condensation along with temperature and humidity changes. What has become even more of a PITA to us is the already alluded to chamber lubricant.
The major D-SLR manufacturers are notorious for selling brand spanking new cameras, pre-loaded with dust. You must try to stay calm, though, because if you send it back and get a second one, the odds are overwhelming that it too will be just as dusty. OK, so let's go to the user manuals. The recommended procedures in most user's guides are actually humorous in how ineffective they are. After doing exactly what was specified, including the oh-so-elegant-and-ever-so-dainty "POOF" from a bulb blower, we could hear the dust-bunnies laughing. We sent our first D-SLR back to the manufacturer for cleaning, and when it returned, it had the exact same number of dust specks as before, 28, to be precise, but they were nice enough to have rearranged all 28. Here's how one manufacturer sent a camera back after a cleaning:
Hearing from others who had the same results with Nikon, Canon, et. al., we realized that this would get us nowhere fast, so we set out to find a good working method of self-cleaning the sensor.
With frustration mounting day by day, we ratcheted it up a couple of notches and went for more power with compressed air. This device stirred up the loose dust particles - some of the dust escaped the chamber, but MOST of it just moved around on the sensor. All of them were no match for the stuck specks. We tried several types of vacuums, including various computer-vacs and a 2.25 horsepower Shop-Vac (yes, I was a wee bit desperate at that point). They performed as poorly as the blowers. Not until later did we find out how risky it is using any of the high-powered blowers and vacuums. Anyone who promises you fantastic results from a vacuum cannot possibly own and clean a D-SLR.
Then, when we were just about to give up, we came across a method which utilized home-made or pre-made sensor swabs, along with methanol. These particular swabs are wrapped with a special lint-free cloth and the tip is moistened with a few drops of methanol. This liquid makes the dust particles stick to the cloth for removal; a dry cloth will only push the dust around the sensor. In addition, methanol turned out to be the greatest weapon against the dastardly "chamber-lube".
EUREKA and GADZOOKS, man!!!! we immediately knew we were onto something.
As you work your way through this tutorial, what we've already touched on will be explained and illustrated in great detail, so don't worry if this is all new to you right now. The important point to keep in mind is that your D-SLR, along with all of your lenses and accessories, are quite a sizeable investment. Sensor maintenance will require you to choose the tools and method necessary to protect the performance of your camera and the integrity of your images - it's a VERY IMPORTANT DECISION.
BUT FIRST.....
At the end of this tutorial, we hope you will be much better able to decide which tools and method to use when you're ready to clean your sensor.
#2 - A Close Look
There are several types of tools you can choose from to clean your sensor. Here's a close look at a couple of the time-proven ones and a few that should be avoided at all costs.
#2 - Sensor Brush
A sensor brush has a static charge placed on the tips of its bristles and then picks up dust particles as it sweeps across the sensor. The most common way to charge a brush is to rustle the filaments with a blower for about 5 to 10 seconds. Are all sensor brushes on the market the same? The brush pictured above uses filaments imported from India and assembled in the United States. Almost every other sensor brush comes straight from China or Germany, pre-assembled with white nylon bristles. These cheaper brushes will not hold their shape very long and will start to splay outwards after a little use.
The beauty of sensor brushes is that they can be used over and over again as long as the filaments are kept clean. Most of our customers use a brush once a day and then wet-clean every week or two, depending on various factors. Sensor brushes help keep loose dust from taking up residence on your sensor and turning into super-glued specks, which will keep your wet-cleaning to a minimum. They're a one-time purchase and will last for years.
GOOD BLOWERS & BAD BLOWERS
Blowers alone cannot clean sensors by themselves, but they do have a prominent part to play by blowing off loose dust particles.
GOOD BLOWERS:
OK, so when is the right time to use a blower and which ones should be used? You need to have a good look at the sensor before you clean it with any wet or dry tool. If you see any particles with the naked eye, then get a bulb blower like the Giottos Rocket and carefully blow off the sensor. You'll hear this mantra repeated throughout this tutorial that the biggest risk in cleaning a sensor is if there are big chunks of debris sitting on the sensor and the Rocket cannot dislodge and remove them. ONLY IN THIS INSTANCE should you use canned air. There is a bit of hysteria about how dangerous canned air is but it has recently been disclosed that many Canon techies depend greatly on it. If you follow these guidelines it is actually very safe:
•The only time to use canned air is when a bulb blower cannot dislodge a big particle.
•Don't shake the can beforehand; there's nothing to "mix.
•When spraying with it, keep it perfectly upright and move the object you're blowing NOT the can.
•Always let a little air out before spraying an optic. Propellant has a tendency to build up towards the valve and will come right out if the can has been sitting for a while
•Don't let the jet-straw get any closer to the sensor than 1" or 1½" or just inside the lens mount.
•Use very short bursts, no more than a one second shot; "freezing" will only occur when you use a prolonged stream of air.
Using these guidelines, we have never had any problems with canned air. If by some chance the canned air cannot remove the dastardly stuck-on specks, try ignoring them for a day or two, in many cases, they will pop off on their own. If you can determine that the speck is a dust mote and NOT a big particle of debris or grit which canned air should be able to remove, then it should be safe to proceed with a wet cleaning. If it definitely is an unmovable piece of grit or you're not sure what to do, then, by all means, send it to the manufacturer for cleaning.
What's brown and sounds like a bell? Dung.
BAD BLOWER:
Foot-pump. How dirt, silt and contaminant-free is the air at floor-level? This device was used to blow off slides way back in the emulsion days, but there is absolutely NO use for it with today's digital cameras. There was an incident where a guy was using one to blow off his sensor when the tip flew off right into the sensor making a nifty scratch. Avoid at all costs.
#3 - Preparing a CopperHill Swab has never been easier!
There are several ways of preparing a SensorSwipe in the CopperHill method: you can use a whole PecPad or cut it into quarters or thirds. If you have large hands, you'll probably do better with a whole pad.
But the easiest method is to use a CopperHill QuikStrip which is simply draped around the SensorSwipe and secured with either a small rubber band or a piece of tape. This way of making a swab removes all of the folding needed with the other methods, it also removes any "bunching up" of the material around the 'Swipe, making it the most streamlined flexible swab on the market. In order to use QuikStrips successfully, you must follow our enclosed directions precisely, otherwise you may have problems.
NOTE: We are now including 6 complimentary QuikStrips in every CopperHill Kit.
#4 - Swabbing Illustration
IMPORTANT: Most of the newer D-SLR's have the feature where you will not be able to raise the mirror for cleaning unless the batteries have a sufficient charge. If your camera does not have this feature, we strongly advise purchasing an AC-adapter. Quite a few people have had to repair the shutter curtain because they relied on batteries to raise the mirror and hold the shutter open in the "Bulb" mode. When batteries give out as you're cleaning the sensor, the shutter can close on the swab. And, again, this is extremely important if you are cleaning an older D-SLR -
USE FULLY CHARGED BATTERIES OR AN AC-ADAPTER IF RAISING THE MIRROR IN THE BULB MODE.
NOTE: The major camera companies' disclaimers regarding self-swabbing say in essence: "Don't even think about doing it yourself or the universe as we now know it will come to a screeching halt!" They are naturally covering their butts because they would have no control of the implements and techniques the general public might use. And they would much rather have you send your D-SLR into them every month or two for cleaning. We've heard they charge anywhere from $25 to $125 (they're not stupid, you know).
IMPORTANT:
Your first step here will be to apply the Eclipse to your PecPad-wrapped SensorSwipe. The Eclipse will come out of it's bottle lightning fast. So fast, in fact, that the last thing you will need to do is to squeeze the bottle. Just tip it over very gradually, and the two drops will come out on their own.
#1 - After applying one or two drops of Eclipse on the tip of your swab, lock up the mirror, then remove the lens. Proceeding very carefully, guide your swab into the corner where you've chosen to start as shown in this photo. There is a rim or sidewall around most sensors which you should be able to see clearly. The idea is to "tuck" the SensorSwipe or Sensor*Swab right into that corner.
#2 - Using pressure maybe equal to writing with a pencil or pen, gently drag the moistened swab across the top half of the sensor, hugging the upper sidewall as you go.
#3 - Complete the stroke by going as far as the sidewall will permit (those of you with sensors without sidewalls, just barely overlap the sensor's edge). This may require a little practice - bringing the tip of the swab (with the dust) all the way to where the low pass filter meets the wall. If you are getting the center clean but are leaving dust at the edges, try moving the pivot point of the swab to get a better angle at the end of the floor (you'll see what I'm talking about once you've swabbed a couple of times). In other words, as you are completing your left to right stroke, tilt your hand slightly to the left; as you complete your right to left stroke, tilt your hand slightly to the right.
#4 - You should now have some dust adhering to the first side of the pad, so after completing the first pass, as shown in frame #3, lift the swab up just far enough to move it into the next position, as shown here in frame #4. In this left/right, right/left configuration, there is no ROTATION of the swab as it is positioned for the second swipe; it is simply lowered to the bottom right corner of the sensor.
#5 - Starting in the lower right corner, use the same steady light pressure to drag the swab all the way to the opposite side of the sensor. This time you'll be hugging the lower sidewall as you make the trip. When we say "hugging" we actually mean getting as close to the wall without pushing on it, or, more acurately, "guiding" on it. Too much pressure against the wall may cause loose strands to come out of the PecPad.
#6 - The key to successful sensor swabbing is keeping the swab flush on the sensor surface and completing each stroke, going as far as the sidewalls permit. Look at the angles of the swab in each of these 6 frames to get some idea of what the goal is. And, again, don't give up on it - some people will pick it right up while others may have more of a learning curve.
#5 - Important Points Before Your First Swabbing
These are a few points we would like to emphasize before you swab for the first time:
#1) Take your time, DON'T RUSH! There is no need to make a mad dash into the chamber with your moistened swab. It is MUCH more important for you to see exactly what you are doing, rather than worrying about ambient dust getting into your camera. Your speed will naturally increase as you go on.
NOTE: We recommend waiting about 5 or 10 seconds after applying the Eclipse to begin swabbing. This will allow a good majority of the liquid to migrate away from the tip, making it less likely to streak. We used to remove the lens and then apply the Eclipse to the swab, but now, it works out perfectly to reverse these two steps.
So, your sequence will be: 1) lock up the mirror; 2) put the one or two drops of Eclipse on the 'Swipe's tip; 3) remove the lens; 4) swab the sensor; and, finally, 5) remount the lens, unlock the mirror, and turn the camera off.
#2) VISIBILITY is the key word in sensor swabbing. The highly reflective "mirrored" surface of the sensor makes it a real challenge to guide your swab into the starting corner. This is just as difficult as trying to poke a fish in a pond with a stick. A good light is mandatory and be extra aware of the extremely small space you will have to negotiate the swab onto the sensor. Looking back on my first swabbing, I now realize I could have established a better orientation of where my head, my hand and the light were, BEFORE I went in to swab for the first time. This is why I strongly recommend doing a dry run with the lens off, just like you were going to swab. Experiment with the amount and position of your light source until you have the best view of the sensor possible. At present, I am using a 150W halogen drafting light ($50 at Staples).
*Also, I cannot stress enough the need to be able to see clearly at close-up range. My eyes are about 1½ feet away from the sensor when I swab, and it's absolutely necessary for me to wear my reading glasses at this distance.
#3) Our own PecPad Strips are the "beesknees" for sensor swabbing, we strongly recommend them over full-size PecPads. Keep the strips and your SensorSwipe in zip-lock bags when not in use.
#4) DO A PRACTICE RUN: make your swab with the PecPad and put 1 or 2 drops of Eclipse/E2 on it just to see how the liquid is absorbed, then wipe a piece of glass or a jewel case with it. Hopefully, you'll see that this is a very BENIGN process which is made slightly difficult only by the very awkward positioning of the sensor in the chamber. You will also see how fast the fluid evaporates in back of the swab (from 1 to 3 seconds). This point is very important because I think a lot of the apprehension about sensor swabbing involves the thought of using a LIQUID to wipe the very intricate electronic sensor. A dry run will confirm that there is virtually NO chance of the Eclipse running or "puddling" on the sensor if you use no more than 2 or 3 drops.
#5) Take a couple of seconds to look at the CCD or CMOS. If you see any specks on your AA filter, try to blow them off with a blower before you swab (I recommend using canned air if possible). DO NOT swab your sensor if you see a speck on it and you cannot blow it off. If you just can't remove it, please send it into the manufacurer for service. This is the one area where you could cause some damage by forcing the issue.
#6) It's a good habit to remove the lens very carefully without a lot of banging against the lens mount. You should position your cam in the most comfortable position for working on the sensor. You can swab with the camera on a tripod at a 45° angle facing up, for example, or you can swab with it laying on its back on your desk, whatever works best for you. There is no need to be a contortionist by swabbing with the camera facing down (unless you're the kind of person who enjoys that sort of thing).
After many years of swabbing sensors, we now favor the camera flat on its back on a desk at 90 degrees. We prepare the SensorSwipe as usual and make the strokes with a sort of "rowing" action with both hands on the 'Swipe. This method somehow gives us much more conrol of the stroke enabling us to get as close to the sidewalls as possible without straying off the sensor surface. Try it, you may see what we're talking about..
#7) Even after years of sensor swabbing, we still enter the chamber with the utmost care and respect for the delicateness of the sensor's components. As you continue on with this process, try to strike the perfect balance of total confidence in what you're doing with an appreciation of the sensor's precision construction.
#8) It has been our experience that cleaning an imaging sensor on a regular basis will greatly reduce the super-stuck dust accumulation. In other words, when these stubborn specks are left to sit on a CCD or CMOS, very similar to leaving that bug-splat on your windshield, they get harder to remove. Therefore, we recommend a methanol swabbing at least every two weeks for ALL D-SLRs. I also recommend washing your car and dog once per season. A sensor brush is the perfect companion to your swabbing tools, because it allows you to gather up a day's worth of loose dust particles BEFORE they can become stuck. It's simple - brush the sensor every day or two and swab the sensor every week or two.
#9) If after swabbing a number of times you are still left with 2 or 3 specks of dust, close the camera up and go out and take some shots. Don't swab again for a day or two. Very often these specks will be loosened after a number of cleaning sessions, so don't press your luck in the beginning. If these spots continue to remain on your sensor, and it is really upsetting to you, PLEASE send it back to the manufacturer for service. Don't get careless and force the issue by applying a pressure equal to a bowling ball. I want you to have a perfectly clean sensor, but, more importantly, I don't want you damaging your sensor, no matter what.
#10) After your first very successful swabbing, you may be like most people and say: "Is that all there is to sensor swabbing? That was so easy, I don't know why I waited this long to swab! Piece-O-Cake!" This dawning should tell you how simple this really is, but, more importantly, it should prove conclusively how ESSENTIAL it is to do the research, to assemble the proper tools and materials and to practice a number of times before you do the real thing. People who take this preparation for granted will most likely have a hard time. But if you continue swabbing with excellent results, be very aware of the dangers ahead of you:
*WARNING* Becoming proficient at this procedure may lead to an unusual phenomenon - an ADDICTION to sensor swabbing. It's accompanied by a relentless determination to maintain ZERO dust on your sensor. This stage we call - "Crossing Over". By the way, once you do cross over, you will NEVER need to revisit this tutorial again, except maybe to say hello. Seriously, though, please check back here from time to time, as we are constantly updating the information contained within.
#11) After crossing over, I don't want to hear any excuses from you - get out there and use the heck out of your D-SLR.
And last, but not least, go have yourself a nice stiff drink, preferably, but not necessarily, after you swab
#6 - Tips & Links
NOTE: This photograph is no doubt the best example of how dust can ruin an image. Microsoft has provided some very nice wallpapers, including this one, Nature3. It was taken with a very dirty D100 in 2004, and I can count at least 14 dust-bunnies.
NOTE:
A prerequisite to talk about "brooming" is the proper terminology. There is an unlimited supply of confusion out there as to locating where the dust is on your sensor as compared to where it appears in your images. In other words, if the dust is in the upper right of a photograph, where exactly is it sitting on your sensor? I want you to forget all about putting names and locations on your sensor as you are in the shooting position. It will make this orientation much, much easier to understand.
#1) The image you see on your computer monitor will have four corners we will refer to as upper left; lower left; upper right; and lower right. Pretty easy so far, right?
#2) When you raise the mirror and remove the lens from your D-SLR, you will be looking into the camera's chamber with the sensor affixed to the back wall. FROM THIS VANTAGE POINT, the sensor will have corners refered to as upper left; lower left; upper right; and lower right. I don't care what names these points were called before you rotated the camera the 180° to look into the chamber - it's irrelevant. What is of primary importance is that you realize what "as you look at it" means. It means "as you look at it", or, "from your own perspective", NOT from the position the sensor had while you were in the shooting position behind the camera. If you follow the directions that follow with these points in mind, you will be able to locate the exact position of the dust on your sensor. I promise. Example: The dust-bunny that is in the upper right of this image is sitting on the lower right of the sensor as you look into the chamber.
Please read this brief thread on this topic:http://www.nikonians.org/dcforum/DCForumID71/16121.html
If you get to the point where you've done everything contained in this tutorial to get rid of your dust, and you're left with one or two specks that act like "kryptonite", you might want to try "brooming" the sensor.
First, determine exactly where the speck(s) is located by using the "up/down" or "one vertical flip" alignment. This means that if your speck is in the upper left of your image, it is actually sitting on the lower left of your sensor AS YOU LOOK AT IT from the front of the camera. Similarly, if it's in the lower right of your image, it's actually sitting on the upper right of your sensor AS YOU LOOK AT IT. Upper center of the image, lower center of the sensor, etc., etc. One vertical flip.
Next, prepare your camera and SensorSwipe in the usual swabbing manner. Remove the lens, then place one drop of Eclipse on one corner of the PecPad. Start swabbing just in the area you determined in the previous step, using only the moistened corner of the pad. Go back and forth here several times (3, 4 or 5). What this does is to concentrate your force right where that little rascule has taken up residence.
Now prepare another SensorSwipe and do a normal swabbing as shown in this tutorial. This is necessary because the brooming will probably move the dust to another area of the sensor.
Check your results and have another stiff drink.
This would probably be considered an advanced tip, only to be attempted after you've acquired quite a bit of experience and a normal blood pressure reading.
Because of the focused pressure, I strongly recommend starting with a light to moderate force with your swab. I think the *most* pressure I've used brooming would be maybe equal to rubbing with a pencil's eraser. Again, this method should only be used as a last-ditch effort when all else hasn't worked.
If brooming still doesn't dislodge the speck(s), it's definitely time to send the camera in for servicing.
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