Sensor test
Sensor dust
Take a photo of a bright sky or a white wall at a small aperture and add it here. We mark dust specks and spots on the sensor in red and tell you whether it needs cleaning.
Photo of a bright surface
Drop the photo here
JPG · PNG · WEBP · RAW (preview)
Your file stays on your device. Nothing is uploaded to a server.
Result
0
Red circles mark the specks we found. In the “Dust enhanced” view, brightness differences are boosted, so even faint dust shows.
The lens flips the image: a speck in the top left of the photo sits in the bottom right of the sensor.
Reading the photo…
Looking for dust…
This browser can't open the file. Upload a JPG straight from the camera.
This is a RAW file, so we checked the JPEG preview stored in it ({w}×{h} px). Fine dust shows better on a full-resolution JPG.
This photo has too much detail or is too dark. Shoot a plain sky or a white wall and focus manually so the image is completely blurred.
We found no dust. The sensor looks clean.
A few faint specks ({n}). That's normal and they only show on a plain sky at f/11 and smaller apertures.
Specks: {n}, clearly visible: {m}. A sensor clean with a blower or at a service would help.
Specks: {n}, clearly visible: {m}. The sensor is very dirty. Factor the cost of a service clean into your price.
Sample: a sky shot at f/16 with a few dust specks.
How to take the test photo
- Set the aperture to f/16 or f/22 and ISO 100. Aperture priority (A or Av) is easiest.
- Point the camera at a clear sky or a plain white wall so it fills the frame.
- Switch the lens to manual focus and turn it fully out of focus. Moving the camera doesn't hurt, it even helps.
- Upload a JPG straight from the camera. From a RAW file we can only check the embedded preview.
Dust or something worse
- Soft grey dots are usually dust. A blower or a sensor clean at a service removes them.
- Lots of small spots at the top of the frame that come back after cleaning are often oil from the shutter. That's a job for a service.
- Spots that move when you change the lens are in the lens, not on the sensor.
Checked the sensor for dust? Look for dead pixels too.
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