Canon EOS 40D vs Canon EOS 20D Astrophotography

This is a full comparison between the cameras Canon EOS 40D and Canon EOS 20D Astrophotography. We compare them by looking at the categories you see below.

Canon EOS 40D
Canon EOS 20D Astrophotography

Manufacturing

These cameras are both manufacturered by Canon.

Canon EOS 40D were released 2007 and Canon EOS 20D Astrophotography was released 2005. That is a 2 years difference. In tech, this period of time can be of interest since technology is always improving etc.

Camera Manufacturer Released
Canon EOS 40D Canon 2007
Canon EOS 20D Astrophotography Canon 2005

Type of camera

Both these cameras are DSLR cameras. No difference there.

Sensors / crop factor

Both these cameras have the same sorts sensor (called "APSC") which means that if you compare the cameras side by side the lenses will also have the same experienced focal length. Neither of the cameras have a Full frame sensor which means that you will get a "crop factor" where the cameras sensor size effect the focal length with a multiplier.

Camera Experienced focal length when using a lens with 50mm focal length (ex a common "50mm f/1.8")
Canon EOS 40D 80 mm (a Canon APS-C sensor have a crop factor / focal length multiplier by * 1.6)
Canon EOS 20D Astrophotography 80 mm (a Canon APS-C sensor have a crop factor / focal length multiplier by * 1.6)

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

Resolution

Canon EOS 40D has a 10,1 MP (Megapixels) resolution while Canon EOS 20D Astrophotography has 8,2 MP. If we break down this in more detail this is the data behind the numbers:

Camera Megapixels Pixel (total) Pixels (width) Pixels (height)
Canon EOS 40D 10,1 MP 10077696 3888 2592
Canon EOS 20D Astrophotography 8,2 MP 8185344 3504 2336

Canon EOS 40D has a 23 % larger resolution than Canon EOS 20D Astrophotography. This could give you more details in the picture but also a possibility to crop more in the pictures, afterwards while editing the pictures, if needed that is.

ISO range

Both of these cameras offers the exact same ISO range. They both have 100 to 3200.

Camera ISO Range
Canon EOS 40D 100-3200
Canon EOS 20D Astrophotography 100-3200

Autofocus and lens compatibility

Both of these cameras have a built-in autofocus motor. Some lenses, that supports autofocus, does not have a autofocus motor of their own but this wont cause any problems with these two cameras.

Lens compatibility chart for Canon EOS 40D
Lens compatibility chart for Canon EOS 20D Astrophotography

Pictures per second

Depending on what you are shooting the FPS, or frames/pictures per second, can definately be of interest. Canon EOS 40D can shoot up to 6,5 pictures per seconds and Canon EOS 20D Astrophotography can shoot up to 5 pictures per seconds.

Camera FPS (Frames per second)
Canon EOS 40D 6,5
Canon EOS 20D Astrophotography 5

Ability to record movies

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

Though, neither Canon EOS 40D or Canon EOS 20D Astrophotography 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, carried around, for several hours at the time.

Canon EOS 40D weighs 822 gr (equal to 1,81 lb) which is 7% heavier than Canon EOS 20D Astrophotography and its 770 gr (or 1,7 lb).

Camera Weight (in gram) Weight (in pounds)
Canon EOS 40D 822 gr 1,81 lb
Canon EOS 20D Astrophotography 770 gr 1,7 lb