As you can see from the top row of images above - the three cameras that I use have different colour shifts with my slightly newer 5D MkII (codename yellow strap... because it has a yellow strap!) displaying quite a strong magenta shift whilst the 7D (codename blue strap, you can guess why) is a little cold and my oldest 5D MkII (red strap) is pretty neutral but maybe 1/3 of an f-stop brighter. I am going to use the red strap body as my basis for changing the colours on the other two a) because it is the most neutral to start with and b) because it has been serviced and cleaned by Canon quite recently.

Obviously these pictures were shot under controlled conditions using the same light source, the same lens on a tripod and have been converted from their RAW using no adjustments whatsoever. I shot multiple frames using each body as a sample just to make sure that there was no shift between frames on the same camera.

The second row of examples are the same RAW files with a white balance applied to exactly the same spot on the white box between Mickey and Minnie's ears. As you can see this gets us a whole lot closer to matching the pictures for colour and this technique is fine when you have something in the frame which allows you to use the eye-dropper tool in Adobe Camera RAW (and in other similar raw conversion applications) and it is also fine when you only have a few images to process in this way. If you shoot an event where there are hundreds of frames, then you would spend an unnecessary amount of time balancing in this way.

The third row of examples utilises one of the cool features of the latest versions of Adobe Camera RAW in either Photoshop or Lightroom (and I'm sure that other software does this too) which allows you to set a default set of settings ranging from white balance to black levels, contrast, saturation to sharpening and noise control for each camera which the software detects from the serial number in the EXIF data as you bring it into the RAW conversion control pane. This is great for a lot of work and is a good option if you usually shoot on a fixed white balance.

These three techniques work for pretty much every digital camera and every scan. Some, more modern and more expensive, cameras allow you to go one crucial step further and that is to tell the camera to automatically shift by a fixed amount of colour for every frame - so that if your camera has a magenta shift like my yellow strap camera you can counterbalance that in camera and your images will show up as they should - no matter which white balance you are using at the time. The next few illustrations are based on a Canon 5D MkII using Canon's own EOS Utility: