Sun 09-Dec-12 12:45 AM | edited Thu 18-Jul-13 12:00 AM by dm1dave
The purpose of this post is to put the DSLR sensor dust issue into perspective and give an overview of digital sensor cleaning tools, cleaning products, and cleaning techniques.
Problem: Dust or lubricant on DSLR camera sensors can create visible spots on photographs.
Cause: Dust can find its way onto a sensor from the outside the camera when changing lenses. Both dust and liquid contaminants can be introduced by poor cleaning techniques.
In some cases dust and liquid contaminants appear to come from within the camera. Some of the D600 cameras, and to a lesser extent the D800 cameras, have dust right out of the box.
Preventative Measures: The most effective way to deal with dust is to ensure it does not reach the sensor. When changing lenses position the camera with the camera chamber pointing down, allowing gravity to help keep dust out of the camera. In windy conditions cover the camera with a coat or sweater when changing lenses.
Clean the outer rim of the camera chamber, and the corresponding lens mounting rim, with a micro cleaning cloth. This will eliminate dust and lubricants that can get into the body of the camera.
Regularly use a rocket blower on the mirror and camera chamber. For dust to get to the sensor, it must first pass the mirror and camera chamber (even if it is coming from within the camera). Any dust particles that you remove from the camera chamber means less potential dust sources for the sensor.
Approach: Use the least invasive cleaning methods first. Only escalate to more invasive methods when necessary. In summary, begin with dry cleaning methods and then move to wet cleaning methods if the dry cleaning fails to solve the problem. Start with a bulb blower. If unsuccessful, move to a sensor brush. If that doesn't work use a sensor pen and a sensor stamp. If these dry methods fail move to a wet cleaning. See the detailed information below about the necessary tools and the proper procedures.
Checking for Dust: There are two methods for checking for dust. You can take a photograph of a clear blue sky or a smooth white wall using a 50mm lens or smaller at f16 or f22. It dust exists it will be seen in the image.
The second method is to use an LED lighted magnified loupe to see the dust. Visible Dust has a great LED lighted 7x loupe ($95).
The advantage of the loupe is that you can see dust right on the sensor, and not indirectly from a photographic image. Also with the loupe you can see dust particles on the mirror and camera chamber, allowing you to remove it with a bulb blower before the dust finds its way onto the sensor. In addition, a loupe eliminates the need to shoot and reshoot test images during the cleaning, allowing for a faster and a more efficient cleaning process.
Perspective: Don't dwell too much on the dust problem. It is a fact of life with the new generation of DSLR cameras with their large megapixels images. Dust will rarely show up in your photographs, but when it does it only requires a sensor cleaning. Don't let microscopic particles of dust stop you from owning one of these fine cameras.
Lenrentals.com has a video demonstrating sensor cleaning techniques on YouTube. It will give you a good overview of the process:
Note: DSLR camera sensors can be damaged. You need to invest in the proper tools, and spend the time learning the proper sensor cleaning techniques. Fortunately there are many video and Web resources that demonstrate the best methods for cleaning a sensor. We will outline these below.
You also need to consult your camera's manual for detailed information about raising the mirror and opening the shutter to access the sensor. Most DSLR cameras have manual sensor cleaning modes accessible from the menu system. This involves locking the mirror in the up position and keeping the shutter open, allowing access to the sensor.
Always begin with a fully charged battery to avoid unexpected mirror drops or shutter closings during cleaning due to a lack of power. Some cameras, like the Nikon D100, require the optional AC power cord to clean its sensor. Consult your manual for the proper procedure.
DRY CLEANING METHODS
Dry cleaning methods employ tools and methods that do not require using liquid cleaners. These techniques are less invasive then wet methods and should be use first.
The safest, least invasive method is to blow dust away using air. Prices range from $10 to $130 for these blowers. All of these tools use the same technique, expose the sensor and use puffs of air to dislodge dust form the sensor. You can also remove dust from the mirror and camera chamber with a bulb blower. Point the camera opening down so that gravity can help pull out the dist particles. On the low end of the price scale is the Giottos Rocket Air Blower ($10). It is a simple bulb blower that works great.
NRD's FireFly is at the top of the cost scale ($130). NRD describes the process as utilizing "a nine-volt battery to 'ionize' the air passing through the body of the Firefly, producing and delivering both positive (+) and negative (-) air ions to the outlet air stream. This assures that the static charges are neutralized, allowing the particulate matter to be blown off by the ionized air stream and flushed out of the camera body."
If you cannot dialogue dust particles with air, you can use specially designed sensor cleaning brushes. Typically you use a bulb blower on the brush bristles to create a static charge. The simple brushes look like an artist's painting brush. The more complex brushes incorporate LED lights and methods to create a static charge on the bristles.
VisibleDust offers the Arctic Butterfly 724 ($126). The Arctic Butterfly 724 has two bright LED lights to help see the sensor. It also has a motor that spins the brush to create a strong static charge on the bristles before touching the sensor. Never use the motor to spin the brush on the sensor.
Note: Be sure to clean the leading edge of the brush with the bulb blower with each pass over the sensor. Also avoid letting the brush touch the outer edge of the sensor. This area may have a light lubricant and you do not want to draw it onto the sensor. Never let the brush touch anything but the sensor, not even the mirror or camera chamber. If a brush is dropped or becomes soiled, VisibleDust sells a liquid brush cleaning solution.
Sensor Pens and Sensor Stamps
Sometimes a particle of dust can become stuck or "welded" to the sensor. The next dry step is to use a Sensor Pen or Sensor stamp. Lenspen has the SensorKlear II ($20). The SensorKlear pen has an articulating head with a sensor cleaning pad.
Dust Aid offers the Dust-Aid Platinum stamp ($30) with 12 replacement pads ($10). The Dust Aid Platinum uses a specially designed pad that you lightly press onto the sensor, removing the dust. The concept is like flypaper for dust.
The following link to the Dust Aid Platinum product page also has very helpful instruction videos for using the stamp.
Note: LensRentals.com recommends that if you use the Sensor Pen you will need to use the Sensor Stamp to remove small particles left by the Pen. See the LensRentals.com video mentioned at the beginning of this post.
WET CLEANING METHODS
If dry cleaning methods are unsuccessful, or if you have oil on your sensor, you will need to employ wet cleaning techniques. Wet methods involve using swabs and cleaning solutions specifically designed for cleaning DSLR sensor. You put a small amount of the liquid on the edge of the swab and draw it across the sensor face. Swabs are used for one cleaning and the discarded.
Dust Aid has the Dust Wand Kit ($40). The kit includes Dust Wands for cleaning any sensor aspect ratio, 3 cloth clips, Ultra Clean liquid and 50 Dust-Cloths. It is designed to dislodge and/or remove welded-on dust and light oils. The following link also has an educational video on the Dust Wand use.
You should employ due diligence by researching and understanding the various vendors and tools available to clean digital camera sensors. It is up to you to choose the right tools at the right cost for you needs. This primer should give you a head start.
In another post someone said that getting sensor cleaning tools is like building a lens kit. You build your cleaning kit over time, getting the tools you need for your particular situation. It is not necessary to go out and buy everything at once. Just get the things you need when you need them.