Dead Pixels in your Shots? by

Posted in Shooting Tips and Tricks

If you do a lot of long exposure photography, especially at night, you'll eventually notice stuck pixels, especially as your camera body ages. These will appear as solid red, blue, or green dots in your photos (RAW or JPEG) that shouldn't be there. In the example below of an 8 second exposure at night, there are dozens of them. I've highlighted a few, although they're hard to miss.


(click to zoom)

These are typically from "dead" pixels in your sensor. This is completely normal and doesn't mean you have a broken camera or sensor.

Most Canon bodies have a method to remove these from the image data it captures, called 'Manual Cleaning.' Don't confuse this with the sensor cleaning process which occurs when you switch your camera on or off. Instead, this process actually internally analyzes the results of a long exposure (with the lens cap on), and internally flags these spots so they won't continue to appear.

You can repeat this process several times, and overall it can take several minutes, especially if you have a lot of them to correct, but afterwards, most if not all of these dead pixels will no longer appear in your shots.

My first run through of this, after taking the example shot above last night, removed every single dead pixel!

This is particularly important if you shoot JPEG instead of RAW, and want to use the photos Straight Out of Camera (SOoC). If you shoot RAW, it's much easier than cloning them out in post!


(Manual Sensor Cleaning, Canon 5DMkIII Menu)

Look for the Manual Sensor Cleaning in your camera menu. The screen will give you instructions, but typically you'll want to leave the camera in this mode for at least 60 seconds, then shut if off.

If anyone has information about this process on Nikon or other bodies, please add it in the comments below, and I'll append it to the article.

Keywords: dead pixels, stuck pixels, long exposure noise, canon menu, sensor noise, dead sensor pixels

~Scott Smith
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