How To Clean DSLR Image Sensor

Back in the old days, we only cleaned our camera body. It was limited to external cleaning and blowing out dust from the mirror & focusing screen. The digital era added another component in that list, i.e. the Image Sensor.  It is also the most delicate part of any DSLR.  If you shoot  in outdoor or change lens frequently, the chances are pretty high that your image sensor will gather some dust, maybe even few stubborn dirt that ruins your images. 

Know When To Clean Image Sensor:

The only thing you need to do is to view your digital image at 1:1 enlargement. Almost all photo viewing / editing software has 1:1 enlargement setting. At 1:1 enlargement, scrutinize the image for tiny black ( or dark) dots or lines. You may not see anything in landscape shots if the whole frame is covered with objects  / trees etc. They are more visible in blue or white cloud sky shot covering the whole frame. The best reference would be the blue sky covering the whole frame, or just a white screen. This is a 1:1 crop of blue sky shot, showing dart in the image sensor.

Tiny dots at 1:1 crop

At 1:1 crop

How To Clean The Image Sensor:

The fist place you should look into is your camera setting menu. If it has a 'clean image sensor' ( most Nikon camera has) in the menu, select that and press 'OK' button. I've no idea what it does internally, but I know it could remove small dust that are not so stubborn. Once, you have done this, take a shot of blue sky ( white cloud is OK too) and view your image in 1:1 magnification.  You are in luck, if the image is clear. If not, read on.

Please note that image sensor is very delicate & sensitive component. It can be easily damaged by a tiny scratch from any foreign object. If you are not sure of handling sensitive electronic component, you must send it to any professional service center for cleaning. Nikon charges only $50 + shipping for cleaning image sensor. However, a damaged image sensor would need replacement that often cost more than $1000 for high end cameras. If you wanna do it by yourself, you risk damaging the sensor.

What You Need To DIY:

The first task is to identify the image sensor size. The full frame camera image sensor is 36 X 24 mm across the brands. Whereas APS-C camera sensor size varies by brand. You will need to get sensor cleaning swab as per your sensor size. Purchase that as per your sensor size. There are few other  items you would need, here is the full list.

1. Sensor cleaning swab as per the sensor size ( at least 2 )
2. Rocket Blower ( also known as blower brush )
3. A small flash light
4. A magnifying glass
5. Lens cleaning solution
6. Fully charged camera battery

The complete cleaning kit I used to clean full frame sensor

The Process:

Insert the fully charge battery in your camera and remove the lens. Turn on the camera and go to the setting menu. Select the option that says 'Lock Mirror Up For Cleaning' and press OK.  This will pop up a dialog that says "When Shutter Release Button Is Pressed, The Mirror Will be Locked UP, Turn the camera off to return to the main menu".

BTW, Nikon cameras will not allow you to perform this step unless the battery is fully charged.  I don't know about canon or other brand, but they must be having similar restriction.

Now, press the shutter release button and verify the mirror is really up. You should be able to see the image sensor directly.

Next hold your camera up, with the opening face down. Gently pump the rocket blower, the nozzle tip should be at least 2 inches away from the sensor. Make sure, your hand do not shake and the nozzle tip of the blower never touches the sensor surface. This will remove all loose dust & dirt.  You should not be needing more than 5 to 10 blows.

Once you are done with blowing, put the camera down on it's back, with the opening face up. Grab the flashlight and magnifier and inspect the sensor. Look at the placed where you see dirt in the image. Even if you don't see anything, you should still do the next step.

Unwrap one of the sensor cleaning swab. It might have instruction printed on the packaging. Gently place the swab at 60 degree angle at one end of the sensor and then slide toward the other end. You will need to make it 120 degree when you reach near the other end of the sensor, but make sure you go all the way, till the end. Now, do a reverse sweep till the start point. Put the swab back in it's wrapper, we might need it soon. This will remove moderately stubborn dirt.

Inspect the sensor with the magnifier and flash light again. If  you are satisfied, switch off the camera, attach a lens, and shoot a image of blue sky or white screen. Transfer the image in your computer, and inspect at 1:1 magnification.  If the dark spot are gone, your sensor is clean.

If you still see dirt from magnifier & light inspection or from 1:1 image on computer, we need to do a wet cleaning. Unwrapped the second new swab and spray it with lens cleaning solution. Now, repeat the step you did with the dry swab. If you saw any stubborn dart from magnifier & light inspection, you can sweep over that spot few more time. Now, put away the wet swab and run the dry swab again first forward and then backward. The chances are very high that all dirt are gone by now.  Only in rear cases, you might need to repeat with first wet and then dry swab. Don't forget to verify with 1:1 magnification in the computer before you close this DIY project. Good luck.

 

Shot the blue sky post cleaning, all stubborn dirt are gone.