Dark spots - sensor toast?

Question

I can't seem to get rid of some very annoying dark spots that are very noticeable under certain lighting conditions. I've taken a test shot of my monitor showing a white background and amped up the contrast and blackness to highlight the problem areas.

I've tried with both a dust blower first, which didn't help, and then some liquid afterwards with a microfiber cloth. I know the problem is the sensor because the same spots persist with different lenses on different backgrounds.

Is this sensor toast or is there still hope here?

If the sensor is toast then what might be the cause of these persistent black spots?

I guess this is one advantage of a DSLR over a system camera like this - the sensor is protected by a mirror, even when swapping lenses.

Answer 1

That really looks like sensor dust. Lots of it. The normal way to get rid of it is to use a purposefully designed cleaning solution and brush. Visible Dust makes the ones I use. You can try those, in case the cleaning you used was not good enough.

The certain lighting conditions should not matter, only the aperture, because sensor dust is more visible at small apertures. It is always there and never move, so if that is not what you see, it is another problem.

It is entirely possible that dust slipped behind the anti-alias filter and you will not be able to clean it, not even a professional photo store. The camera manufacturer however can service it and they usually but not always charge a fee for that.

Based on what you tried and the amount of dust, I would go straight to a service center.

Answer 2

That's dust, not toast. :)

Since you've tried liquid cleaning yourself, it's possible that

• that didn't work (in which case you could try a professional cleaning)
• something is under the filter that covers the sensor, which would be worse and probably require factory service.

I'd try the first option first.

Answer 3

It's dust. As for the wet clean it doesn't always come out perfect the first time. There has literally been some shoots where afterwards I had to use about 5 swabs before the sensor was spotless.

Note: Don't use a microfibre cloth to clean a sensor. They are not good enough for sensors. Buy a wet clean kit, follow the instructions on how to use the swabs effectively. You should also use a blower to remove all dust from inside the camera body prior to wet cleaning the sensor.

Answer 4

I've tried with both a dust blower first, which didn't help, and then some liquid afterwards with a microfiber cloth. I know the problem is the sensor because the same spots persist with different lenses on different backgrounds.

A dust blower... - Many people like them a lot, in my case it deposited yet more dust on the sensor. A common tip in any case is to give it a few puffs beforehand to get rid on any dust. Plus, apparently household ones contain talcum powder - so I hope you used one that was free of any such stuff?

As to the liquid cleaning: Sensor cleaning takes place with a cleaning fluid - many people, me included - use isopropanol and some use different solvents as well. (I saw methanol mentioned on fotocommunity.de, but contrary to isopropanol, methanol is toxic.) A cleaning solution can thus be obtained either from a pharmacy or bought as a dedicated sensor cleaning solution.

Next point, a microfibre cloth? Good grief... there are dedicated singled use (!!) sensor swabs to clean a sensor, individually packed. And even if you use any other methods, all wipes that are used to clean the sensor are single use only. The exception is a sensor brush to remove light dust. Having said that, if a blower didn't remove any dust, a brush might not be enough.

Given the amount of dirt on your sensor, I would highly recommend to have it sent off to the manufacturer for cleaning as it is the best guarantee for getting a clean sensor back. (A dedicated service may suffice as well.)