Canon EOS 20D Astrophotography vs Canon EOS 40D

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

Manufacturing

These cameras are both manufactured by Canon.

Canon EOS 20D Astrophotography were released 2005 and Canon EOS 40D was released 2007. That is a 2 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 40D 2007

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 40D 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 40D has 10,1 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 40D 10,1 MP
10077696 pixels
3888 x 2592

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

ISO range

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

Camera ISO Range
Canon EOS 20D Astrophotography 100-3200
Canon EOS 40D 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 Canon EOS 20D Astrophotography
Lens compatibility chart for Canon EOS 40D

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 40D can shoot up to 6,5 pictures per seconds.

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

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 40D 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 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
Canon EOS 20D Astrophotography 770 gr
1.7 lb
Canon EOS 40D 822 gr
1.81 lb

Canon EOS 20D Astrophotography vs Canon EOS 40D Specs

Below you will find the complete and detailed technical specs for both Canon EOS 20D Astrophotography and Canon EOS 40D, next to each other. Each category of data is a link to an article covering the subject, giving you a deeper understanding so you can better understand the strengths and weaknesses of the two camera models.

Product
Canon EOS 20D Astrophotography
Canon EOS 40D
Name Canon EOS 20D Astrophotography Canon EOS 40D
Manufacturer Canon Canon
Release Date and Price
Canon EOS 20D Astrophotography
Canon EOS 40D
Release Year 2005 2007
Release Date 2005-06-01 2007-08-20
MSRP 1499 USD 1299 USD
Buy it today
Camera Type
Canon EOS 20D Astrophotography
Canon EOS 40D
Camera Type DSLR DSLR
Sensor
Canon EOS 20D Astrophotography
Canon EOS 40D
Sensor Size APS-C (approx 22.3 x 14.9 mm) APS-C (approx 22.3 x 14.9 mm)
Sensor Type CMOS CMOS
Resolution 3504 x 2336 pixels 3888 x 2592 pixels
Megapixels 8,2 MP 10,1 MP
Image Processor DIGIC 2 DIGIC 3
Image
Canon EOS 20D Astrophotography
Canon EOS 40D
ISO Range 100 - 3200 100 - 3200
White Balance Presets 6 6
Custom White Balance Yes Yes
Image Stabilization No No
Image Stabilization CIPA Rating 0 stops 0 stops
Uncompressed format RAW RAW
Optics & Focus
Canon EOS 20D Astrophotography
Canon EOS 40D
Autofocus Motor Yes Yes
Autofocus Phase Detect
Multi Area
Selective Single Point
Single
Continuous
Phase Detect
Multi Area
Selective Single Point
Single
Continuous
Focus Points 9 9
Lens Mount Canon EF
Canon EF-S

See Compatible Lenses
Canon EF
Canon EF-S

See Compatible Lenses
Focal Length Multiplier APS-C Sensor
1.6x multiplier
Example:
24 mm becomes 38 mm
50 mm becomes 80 mm
100 mm becomes 160 mm
200 mm becomes 320 mm
APS-C Sensor
1.6x multiplier
Example:
24 mm becomes 38 mm
50 mm becomes 80 mm
100 mm becomes 160 mm
200 mm becomes 320 mm
Screen & Viewfinder
Canon EOS 20D Astrophotography
Canon EOS 40D
Articulated LCD Fixed Fixed
Screen size 1.8” 3”
Screen dots 118000 230000
Touch screen No No
Screen type N/A N/A
Live view No Yes
Viewfinder Type Optical (pentaprism) Optical (pentaprism)
Viewfinder Coverage 95% 95%
Viewfinder Magnification 0.9× (0.56× 35mm equiv.) 0.95× (0.59× 35mm equiv.)
Viewfinder Resolution N/A N/A
Photography features
Canon EOS 20D Astrophotography
Canon EOS 40D
Frames per second 5 fps 6,5 fps
Minimum Shutter Speed 30 seconds 30 seconds
Maximum Shutter Speed 1/8000 seconds 1/8000 seconds
Built-in Flash Yes Yes
Built-in Flash Range 12 meters 12 meters
External Flash Yes Yes
Self-Timer Yes Yes
Time-lapse Yes Yes
Metering modes Multi
Center Weighted
Partial
Multi
Center Weighted
Spot
Partial
Exposure Compensation +/- 2 (at 1/3 EV, 1/2 EV steps) +/- 2 (at 1/3 EV, 1/2 EV steps)
Videography features
Canon EOS 20D Astrophotography
Canon EOS 40D
Video recording No No
Video format N/A N/A
Video resolution N/A N/A
Built-in Microphone No No
Built-in Speakers No No
Storage
Canon EOS 20D Astrophotography
Canon EOS 40D
Memory Card Compact Flash
Compact Flash
Connectivity
Canon EOS 20D Astrophotography
Canon EOS 40D
HDMI Output No No
Microphone Port No No
Headphone Port No No
Wireless No No
Remote Control Yes (N3 connector) Yes (N3 connector)
GPS No No
Body & Dimensions
Canon EOS 20D Astrophotography
Canon EOS 40D
Enviromentally sealed No No
Battery Battery Pack Battery Pack
Battery Details Battery Pack BP-511A
Litium-Ion (Li-Ion) BP-511
Battery Life (CIPA) 1000 shots 800 shots
Width 144 mm 146 mm
Height 106 mm 108 mm
Depth 72 mm 74 mm
Weight 770 gram 822 gram