Camera & Lens Experiments: Noise

Cameras: Canon 5D Mark III, Canon Rebel T2i

Lens: Canon EF 50mm f/1.2 L


Comparing noise in a properly exposed image from a full-frame camera to a crop sensor camera

ISO 6400 is quite high and not typically used in most photographing applications, but you can see how the 5D Mark III handles high ISO quite well and still produces a usable image, while the Rebel T2i produces a very noisy, muddy, poor-quality image at ISO 6400. The difference in overall exposure may be attributed to slightly changing window light but it might have something to do with the camera sensor (I’m not sure). I did this test at varying ISO settings on both cameras, and I even noticed a slight difference at ISO 400. It became very apparent at ISO 1600, and then increasingly apparent the higher I set the ISO. [Click image for larger view]



Comparing noise in an underexposed image from a full-frame camera to a crop sensor camera

The results are even more pronounced when dealing with an image that was quite underexposed in camera and editing it to increase the exposure in post. This introduces even more noise and reduces the quality even more, especially on the crop sensor camera. Still, the full-frame camera can produce a usable image this way. Sometimes I underexpose an image a little in order to retain highlights, and the shadows are easily fixed with editing. [Click image for larger view]





























Comparing noise in an image from an underexposed edited RAW file to an underexposed edited Jpeg file

Shooting in Jpeg just makes for a mess, especially if you have to fix exposure and reduce the noise in editing. A RAW file has so much more data to work with. The image shot in Jpeg becomes extremely soft and blotchy when edited. Shooting in RAW is not just for when you underexpose or overexpose an image; a Jpeg made in camera already has suffered data loss and has the camera’s own edits applied. From my experimentation, I could see the quality difference between the properly exposed RAW and Jpeg images as well. There was a loss of detail in the Jpeg image. [Click image for larger view]




























Roxanne is a Fond du Lac photographer.



  1. Cyndie says:

    This is SUPER helpful info!
    Thank you for sharing!

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