On Canon EOS cameras lower ISO settings have less noise.
The situation with Video noise is a little different to what you expect. ISO 160 has lower noise than ISO 100 (the lowest setting). In fact it has been found that the order for lowest noise to highest is:
160, 320, 640, 100, 200, 400, 800, 1250, 125, 250, 500, 1000, 1600, 2500, 2000, 3200, 4000, 5000, 6400
Is this true for Photographs?
I did a test of the ISO noise of a Canon 60D
I took a series of photos with a constant Aperture of f/16 so the focus and depth of field remained constant.
I took a picture at each ISO from 100 to 640o adjusting the shutter speed for correct exposure.
I used a grey card in the scene to get a smooth neutral color to check for luminance (brightness noise) and chroma (color) noise.
This is the scene:
(click image for full size)
I took a small cropped area (blue outline) from each photo. I set an exposure value of 2 in Adobe Photoshop to brighten the image a little to make the noise more visible.
Below is the image comparing the different ISO settings – once again click image for full size version.
To me it seems that ISO 100 has the least noise. ISO 100, 125 and 160 seem very close with not much difference but overall it seems that for photos the noise level increases with ISO in order from 100 to 6400.
Have a look at the large image and see what you think.
You are welcome to comment below.