Cleaning the Image Sensor in a DSLR Camera

Basically, is this a DIY job, or a job for the professionals ?

The image below illustrates my problem. There is a “smudge” towards the top left corner of the image. It’s been there for some time, but I only noticed it a couple of days ago when viewing photos on my Pioneer Kuro. And even then, only with photos incorporating blue sky in the top left corner. I have swapped lenses - smudge is always there.

I have looked back through my photos and discovered that the smudge appeared whilst in Canada. No smudge on afternoon of 12th September 2017. Appeared in first photo of morning 13th September 2017. Smudge looks remarkably consistent ever since.

Is this most likely dirt of some sort, or a defect in the image sensor.

Likely cost of cleaning ? and any recommended cleaning firms ?

Camera is still under extended guarantee from Grays of Westminster, but probably not for full parts and labour. I am still looking for the guarantee documentation, I only have the receipt at present confirming “5 year guarantee”, dated 17th August 2017.

I will, of course, telephone Grays on Monday, but initial thoughts here might be helpful.

Many thanks,

In the first instance, use something like the Giottos Rocket blower to see if that will dislodge the dust spot. If not, then it can be done yourself, but I always get a professional to do it for me. Easy for me as I have a tame professional who works for beer. :beer::grin:

It doesn’t look like a fault, just a bit of dirt. Easily to solve, but actually it’s pretty tricky cleaning a sensor properly yourself, if you don’t have the right gear and never done it before. It’s easy to make a pig’s ear of it.

Thank you Graeme and Count.d. Very reassuring that it’s probably dirt that can be removed.

I don’t have any previous experience nor any specialist equipment, so looks like it’s going to involve a professional, rather than risk a pig’s ear !


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…in the meantime most photo software have the capability to remove a spot on the photo. I use photoshop and Nik Collection 2 by DxO for post processing.

I do usually carry a Giottos Rocket blower with me since I use prime lenses and the blower comes in handy when changing lens. I have had my sensor cleaned by a professional at the camera store when needed.

Hi Seakayaker, I had wondered about post process adjustment for removing “blemishes” eg smudges. At present my equipment, skill and time wouldn’t be able to cope.

So I am hoping to locate a reliable cleaning company and hoping that will solve the issue.

Of course, I will be looking to improve my processing skills and equipment so that I can “salvage” the past two years of damaged photos. Fortunately, on most of them, the smudge isn’t at all obvious.


Definitely talk to Grays about it. If the sensor needs cleaning they can arrange and they use a company near Clapham Junction which is an authorised service centre for Nikon. As I recall, the charge is about £25 but it’s a few years since I used them.

Modern Nikon DSLRs have a sensor self- cleaning function (which I think vibrates the sensor) so worth checking whether yours does.

In any case my experience of Grays has always been excellent and I wouldn’t hesitate to seek advice from them.

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Thank you David.

The weather is bad today, so no flight training at present. I therefore rang Grays a few moments ago.

As you say, very helpful. They suspect cleaning the sensor is what’s required and advised me to contact a firm called Fixation just down the road from them and across the river. They said that the last time they checked’ the price was about £35 for a DX sensor and £65 for an FX sensor. No need to book, just turn up and the job is done while you wait, c. an hour.

I’ll give Fixation a call on Monday and see what they say. I’d rather leave this to experts than try a DIY job !

The camera does have a self-cleaning mode and I have tried that, but no joy. This smudge is stubborn !


Hi Don
Yes it’s Fixation I was thinking of, but the price has obviously gone up. Anyway they will do a proper job though. You can easily walk there from Clapham Junction railway station (assuming they haven’t moved since I went there last).

Unit C, 250 Kennington Road is what Grays said. A quick look on Google maps and it’s only a short walk from Grays.

I think the £35 (or whatever it turns out to be) will be the least part of the evnt. Mrs D will no doubt wish to squeeze in a theatre show and dinner with our youngest daughter and son-in-law. :sunglasses:

Hmm dredging back into my memory, it might well have been near Vauxhall rather than near Clapham Junction. Anyway as you say, it’s walkable. Good luck with the overall bill for the day!



Yes Kennington Lane (not Kennington Road), just looked it up more carefully.

I often combine Grays and another outfit nearby in Cambridge Street when i’m in that area, so a brisk walk across the river to Fixation shouldn’t be too much effort.

I’ll report back on the success (or otherwise) of the visit !


Remove the brush part and you are left with a gentle blower. Point the camera down and blow gently at the four corners of the sensor. Lower the mirror while the camera is still facing down.

I try not to replace lenses outdoors and at home it is always done while the camera is pointing down. It is a little harder for the dust to travel up. I also always make sure that the rear element of the lens is perfectly clean before mounting it.

By the shape of the smudge, being out of focus, we can tell that the material is not smeared on the sensor but more likely just resting on it so a blower should do the job.


Agree with the above.

If that does not shift it, it is actually not difficult to clean the sensor if approached with care and there are several good kits around. But, though it is not difficult, it can be nervewracking especially the first time.

Hi Haim,

Many thanks for your advice and assessment. The assessment is very re-assuring, I was concerned that the sensor or something else might need replacement. Let’s hope not.

I only have one lens for the camera, a 16 - 80 mm Zoom so I have never removed it in the field. Last week I borrowed a friend’s lens simply to eliminate the possibility of a lens defect or dirt.

Mrs D likes to go up to London to see a show and to go out for dinner with our daughter so despite my comments above, it’s no big deal to drop the camera off at Fixation and I will feel much more at ease doing this than trying to clean the sensor myself. Having read the User’s Handbook, one or two Internet articles and your comments, i’ve no doubt that what’s involved is straight forward, but for c.£35 I would rather get it done this time by somebody who knows what they are doing.

Now, i’f you lived within 100 miles of Newbury UK or Vernon BC I would know exactly what to do :sunglasses:

My post to Haim crossed with yours PW.

It’s the nrevewracking bit that springs to mind, give me a below-average student on the approach (or not quite) anytime !!

Often marks are a bit of dust which can be GENTLY blown away with the camera pointing downwards (to avoid the dust being blown into the camera). But marks happen and it is highly unlikely that there is any problem with the sensor itself. Often you will only notice them in pictures when using smaller apertures.

But it is also always worth checking the lens. I was convinced I had a mark on the sensor last week until I realised that it was only appearing with one particular lens. I put the lens under a bright light and had a good look but couldn’t see anything. I cleaned it anyway and, lo and behold, problem solved!

I only have one lens for this camera, so I borrowed a second lens from a friend and took half a dozen photos of the sky with each lens.

The same smudge is still there with my friend’s lens, So QED the smudge is due to the camera. I think.

Hi Don, Another thumbs up for Fixation here.


Thanks Chris. I’ll be giving them a call tomorrow or Tuesday.

Cheers, Don

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