Why do I have a red dot in every photo?

Question

Every picture that I took today have a red dot on the same place in every photo. It looks like a monitor "pixel error". Is just the lens dirty or did something bad happen to my cam?

Here some samples. Best mode to detect the dot is download the picture in original size (click the (i) then download)

Answer

You're exactly right — it's the same thing as a monitor pixel error, but on your camera's sensor rather than on an LCD screen.

You can either fix it in post-processing (automatically, with many RAW-processing packages) or have it mapped out with the camera's firmware.

If you're lucky, your camera model includes a built-in feature to do that yourself in the field; failing that, it's almost always covered under warranty service.

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