Sony a100 vs Canon EOS 20D Astrophotography

This is a full comparison between the cameras Sony a100 and Canon EOS 20D Astrophotography. We compare them by looking at the categories you see below.

Sony a100

Canon EOS 20D Astrophotography

Manufacturing

Sony a100 is manufacturered by Sony but Canon EOS 20D Astrophotography is from Canon. Both Sony and Canon are well known brands though.

Sony a100 were released 2006 and Canon EOS 20D Astrophotography was released 2005. That is a 1 years difference. In tech, this period can be of interest since technology is always improving, etc.

Camera	Released
Sony a100	2006
Canon EOS 20D Astrophotography	2005

Type of camera

Both these cameras are DSLR cameras. No difference there.

Sensors / crop factor

These cameras have different sensors. Sony a100 has a "Sony APS-C"-sensor while Canon EOS 20D Astrophotography has a "Canon APS-C"-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 **
Sony a100	75 mm Sony APS-C sensor Crop factor/focal length multiplier by * 1.5
Canon EOS 20D Astrophotography	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 (Sony)
Camera selection can affect the focal length (Canon)

Resolution

Sony a100 has a 10 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
Sony a100	10 MP 10036224 pixels 3872 x 2592
Canon EOS 20D Astrophotography	8,2 MP 8185344 pixels 3504 x 2336

Sony a100 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, afterward while editing the pictures, if needed that is.

ISO range

Canon EOS 20D Astrophotography has a larger ISO-range than Sony a100. Canon EOS 20D Astrophotography has an ISO range that stretches from 100 to 3200 while Sony a100 has 100 to 1600.

Camera	ISO Range
Sony a100	100-1600
Canon EOS 20D Astrophotography	100-3200

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 Sony a100
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 definitely be of interest. Sony a100 can shoot up to 3 pictures per seconds and Canon EOS 20D Astrophotography can shoot up to 5 pictures per seconds.

Camera	FPS (Frames per second)
Sony a100	3
Canon EOS 20D Astrophotography	5

Ability to record movies

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

Though, neither Sony a100 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, or carried around, for several hours at a time.

Canon EOS 20D Astrophotography weighs 770 gr (equal to 1.7 lb) which is 21% heavier than Sony a100 and its 638 gr (or 1.41 lb).

Camera	Weight
Sony a100	638 gr 1.41 lb
Canon EOS 20D Astrophotography	770 gr 1.7 lb