EOS 90D Camera sensor scratches

[Sadia]

Hello,

I recently returned from an African safari and needed to clean my lens and camera body. I did everything fine, but once I opened the camera cap and looked at the sensor, I was shocked to see so many scratches (photo attached)! Even though my pictures came out just fine, I was curious to examine (search for spots in the image) if there were any marks on the white paper photo. I checked out some videos on how to do a white paper test to check for spots in the sensor. The white paper photo has no mark on it that I can see (attached). 

I'm wondering if the scratches are common for DSLR cameras. I bought the Canon 90D last year, and it has been great so far. Please let me know if this is something concerning.

Thank you! 

DSLR sensorwhite paper test

[Sadia]

Thank you, Rick. I used only the air puffer. Didn't have the courage to do anything more without knowing it 100%. 

[ebiggs1]

Agree with Rick and John.  You can't actually see or get to the sensor without holding the mirror up out of the way. There is a menu option to do that. From your post I would encourage you to have a pro do the cleaning inside the mirror box. Its not hard but it can be for a first timer.

[Sadia]

I will search for a pro to check it. For now, the air puffer is good enough since my photographs came out fine. Thank you 🙂

[jaewoosong]

What "air puffer" are you using?  Is it like canned air spray or a manual bulb you have to squeeze?  When I looked at the picture, it looked like some liquid that was pushed with a blast of air.  Canned air has liquid propellant that can deposit some liquid on the mirror surface and the blast of air can spread that liquid around on the surface.  This can happen when people tilt the canned air duster sideways or upside down, allowing some of the compressed liquid to be release with the gas.  The only blower you should be using is a manual bulb blower inside your camera.

never use canned air blower

[Sadia]

I used the manual bulb. I watched several videos before cleaning and most videos warned not to use the canned air spray. 

Thank you!

[Waddizzle]

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@jaewoosong wrote:

 Canned air has liquid propellant that can deposit some liquid on the mirror surface and the blast of air can spread that liquid around on the surface.  This can happen when people tilt the canned air duster sideways or upside down, allowing some of the compressed liquid to be release with the gas.  The only blower you should be using is a manual bulb blower inside your camera.

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Canned air does not have “liquid properties.”  What you are seeing is condensation caused by the pressure gradient between ambient air and the pressurized canister.  Condensation almost always occurs with longer, sustained sprays, instead of short bursts.

I totally agree that canned air is not suitable for cleaning DSLRs.

[Tronhard]

A novice came to me with a severely damaged shutter - he had taken to the camera with a can of compressed air that got under the shutter and destroyed it.  SERIOUSLY TO BE AVOIDED.

[jaewoosong]

Canned air is compressed hydrocarbon gas in liquid form.  If used/dispensed improperly, such as sideways or upside down, the liquid gas can be dispensed and freeze objects in blast radius (including moisture in air) before it boils off and reverts back to gas form.

Gas duster - Wikipedia

[ebiggs1]

You do need a pro to clean it and Canon is the best service people.

[Waddizzle]

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@ebiggs1 wrote:

You do need a pro to clean it and Canon is the best service people.

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I would hope that it is dust.  It looks more like something hit it, to me.