On the various Canon forums, many people are extremely happy about the low noise produced by the Canon 7D. But there are also many people extremely unhappy with the noise produced by the 7D and blame the Canon sensor. 18 Megapixels, on such as small sensor, APS-C, is the equivalent to 28.8 megapixels on a full frame camera. No other APS-C camera has such a high density. People blame the noise on the sensor density.

ISO settings

The Canon 7D has the following ISO setting:

  • 100
  • 125
  • 160
  • 200
  • 250
  • 320
  • 400
  • 500
  • 640
  • 800
  • 1000
  • 1250
  • 1600
  • 2000
  • 2500
  • 3200
  • 4000
  • 5000
  • 6400
  • H1 of 12800

That’s ISO 100 to 6400 in 1/3 increments. In fact, it’s not. The actual ISO speeds are:

  • 100
  • 200
  • 400
  • 800
  • 1600
  • 3200
  • 6400

So what happened to the rest, like ISO 125 or ISO 160 or ISO 2500? They don’t exist! In fact the ISO 125 is actually ISO 100 under-exposed by 1/3 of a f/stop. ISO 2500 is actually ISO 1600 under-exposed by 2/3 of an f/stop.

  1. Noise is greatly enhanced when under-exposing.
  2. Only use the full stops settings when setting the ISO.

Custom settings

If you set the: “C.Fn I -2ISO speed setting increments to 1, you will only see the full ISO stops.