Canon EOS 20D Astrophotography vs Canon EOS 450D

This is a full comparison between the cameras Canon EOS 20D Astrophotography and Canon EOS 450D. We compare them by looking at the categories you see below.

Canon EOS 20D Astrophotography

Canon EOS 450D

Manufacturing

These cameras are both manufactured by Canon.

Canon EOS 20D Astrophotography were released 2005 and Canon EOS 450D was released 2008. That is a 3 years difference. In tech, this period can be of interest since technology is always improving, etc.

Camera	Released
Canon EOS 20D Astrophotography	2005
Canon EOS 450D	2008

Type of camera

Both these cameras are DSLR cameras. No difference there.

Sensors / crop factor

Both these cameras have the same sorts of sensor (called "Canon APS-C") which means that if you compare these cameras side by side the lenses will also have the same experienced focal length. Neither of the cameras has a Full frame sensor which means that you will get a "crop factor" where the camera's sensor size affect the focal length with a multiplier.

Camera	Focal length, 50mm f/1.8 **
Canon EOS 20D Astrophotography	80 mm Canon APS-C sensor Crop factor/focal length multiplier by * 1.6
Canon EOS 450D	80 mm Canon APS-C sensor Crop factor/focal length multiplier by * 1.6

** 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 20D Astrophotography has a 8,2 MP (Megapixels) resolution while Canon EOS 450D has 12,2 MP. If we break down this in more detail this is the data behind the numbers:

Camera	Megapixels
Canon EOS 20D Astrophotography	8,2 MP 8185344 pixels 3504 x 2336
Canon EOS 450D	12,2 MP 12166656 pixels 4272 x 2848

Canon EOS 450D has a 49 % 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, afterward while editing the pictures, if needed that is.

ISO range

Canon EOS 20D Astrophotography has a larger ISO-range than Canon EOS 450D. Canon EOS 20D Astrophotography has an ISO range that stretches from 100 to 3200 while Canon EOS 450D has 100 to 1600.

Camera	ISO Range
Canon EOS 20D Astrophotography	100-3200
Canon EOS 450D	100-1600

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 20D Astrophotography
Lens compatibility chart for Canon EOS 450D

Pictures per second

Depending on what you are shooting the FPS, or frames/pictures per second, can definitely be of interest. Canon EOS 20D Astrophotography can shoot up to 5 pictures per seconds and Canon EOS 450D can shoot up to 3,5 pictures per seconds.

Camera	FPS (Frames per second)
Canon EOS 20D Astrophotography	5
Canon EOS 450D	3,5

Ability to record movies

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

Though, neither Canon EOS 20D Astrophotography or Canon EOS 450D 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 20D Astrophotography weighs 770 gr (equal to 1.7 lb) which is 47% heavier than Canon EOS 450D and its 524 gr (or 1.16 lb).

Camera	Weight
Canon EOS 20D Astrophotography	770 gr 1.7 lb
Canon EOS 450D	524 gr 1.16 lb