Canon EOS 100D vs Canon EOS 1D Mark III

This is a full comparison between the cameras Canon EOS 100D and Canon EOS 1D Mark III. We compare them by looking at the categories you see below.

Manufacturing

These cameras are both manufactured by Canon.

Canon EOS 100D were released 2013 and Canon EOS 1D Mark III was released 2007. That is a 6 years difference. In tech, this period can be of interest since technology is always improving, etc.

Camera Released
Canon EOS 100D 2013
Canon EOS 1D Mark III 2007

Type of camera

Both these cameras are DSLR cameras. No difference there.

Sensors / crop factor

These cameras have different sensors. Canon EOS 100D has a "APSC"-sensor while Canon EOS 1D Mark III has a "APSH"-sensor, and their difference in sensors will also affect the crop factor and experience focal length. See the table below.

Camera Focal length, 50mm f/1.8 **
Canon EOS 100D 80 mm
Canon APS-C sensor
Crop factor/focal length multiplier by * 1.6
Canon EOS 1D Mark III 65 mm
Canon APS-H sensor
Crop factor/focal length multiplier by * 1.3

** Experienced focal length when using a lens such as a common "50mm f/1.8"

Learn more about crop factor and focal length multiplier here:
Camera selection can affect the focal length (Canon)

Resolution

Canon EOS 100D has a 18 MP (Megapixels) resolution while Canon EOS 1D Mark III has 10,1 MP. If we break down this in more detail this is the data behind the numbers:

Camera Megapixels
Canon EOS 100D 18 MP
17915904 pixels
5184 x 3456
Canon EOS 1D Mark III 10,1 MP
10077696 pixels
3888 x 2592

Canon EOS 100D has a 78 % larger resolution than Canon EOS 1D Mark III. This could give you more details in the picture but also a possibility to crop more in the pictures, afterward while editing the pictures, if needed that is.

ISO range

Canon EOS 100D has a larger ISO-range than Canon EOS 1D Mark III. Canon EOS 100D has an ISO range that stretches from 100 to 12800 while Canon EOS 1D Mark III has 50 to 6400.

Camera ISO Range
Canon EOS 100D 100-12800
Canon EOS 1D Mark III 50-6400

Autofocus and lens compatibility

Both of these cameras have a built-in autofocus motor. Some lenses, that support autofocus, do not have an autofocus motor of their own but this won't cause any problems with these two cameras.

Here is a complete overview of which lenses work with each camera:
Lens compatibility chart for Canon EOS 100D
Lens compatibility chart for Canon EOS 1D Mark III

Pictures per second

Depending on what you are shooting the FPS, or frames/pictures per second, can definitely be of interest. Canon EOS 100D can shoot up to 4 pictures per seconds and Canon EOS 1D Mark III can shoot up to 10 pictures per seconds.

Camera FPS (Frames per second)
Canon EOS 100D 4
Canon EOS 1D Mark III 10

Ability to record movies

It is becoming more and more popular to record movies with digital cameras.

Though, neither Canon EOS 100D or Canon EOS 1D Mark III can shoot movies so if that is a functionality that you are really looking for you should look elsewhere.

Weight

The weight of the camera can be an extremely important factor, especially if the camera is about to be used, or carried around, for several hours at a time.

Canon EOS 1D Mark III weighs 1155 gr (equal to 2,55 lb) which is 184% heavier than Canon EOS 100D and its 407 gr (or 0,9 lb).

Camera Weight
Canon EOS 100D 407 gr
0,9 lb
Canon EOS 1D Mark III 1155 gr
2,55 lb