Canon EOS Rebel XTi vs Canon EOS 20D Astrophotography

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

Manufacturing

These cameras are both manufactured by Canon.

Canon EOS Rebel XTi 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
Canon EOS Rebel XTi 2006
Canon EOS 20D Astrophotography 2005

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 Rebel XTi 80 mm
Canon APS-C sensor
Crop factor/focal length multiplier by * 1.6
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 (Canon)

Resolution

Canon EOS Rebel XTi 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
Canon EOS Rebel XTi 10,1 MP
10077696 pixels
3888 x 2592
Canon EOS 20D Astrophotography 8,2 MP
8185344 pixels
3504 x 2336

Canon EOS Rebel XTi 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 Canon EOS Rebel XTi. Canon EOS 20D Astrophotography has an ISO range that stretches from 100 to 3200 while Canon EOS Rebel XTi has 100 to 1600.

Camera ISO Range
Canon EOS Rebel XTi 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 Canon EOS Rebel XTi
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. Canon EOS Rebel XTi 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)
Canon EOS Rebel XTi 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 Canon EOS Rebel XTi 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 38% heavier than Canon EOS Rebel XTi and its 556 gr (or 1.23 lb).

Camera Weight
Canon EOS Rebel XTi 556 gr
1.23 lb
Canon EOS 20D Astrophotography 770 gr
1.7 lb

Canon EOS Rebel XTi vs Canon EOS 20D Astrophotography Specs

Below you will find the complete and detailed technical specs for both Canon EOS Rebel XTi and Canon EOS 20D Astrophotography, 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 Rebel XTi
Canon EOS 20D Astrophotography
Name Canon EOS Rebel XTi Canon EOS 20D Astrophotography
Manufacturer Canon Canon
Release Date and Price
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
Release Year 2006 2005
Release Date 2006-08-24 2005-06-01
MSRP 799 USD 1499 USD
Buy it today
Camera Type
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
Camera Type DSLR DSLR
Sensor
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
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 3888 x 2592 pixels 3504 x 2336 pixels
Megapixels 10,1 MP 8,2 MP
Image Processor DIGIC 2 DIGIC 2
Image
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
ISO Range 100 - 1600 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 Rebel XTi
Canon EOS 20D Astrophotography
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 Rebel XTi
Canon EOS 20D Astrophotography
Articulated LCD Fixed Fixed
Screen size 2.5” 1.8”
Screen dots 230000 118000
Touch screen No No
Screen type TFT LCD N/A
Live view No No
Viewfinder Type Optical (pentamirror) Optical (pentaprism)
Viewfinder Coverage 95% 95%
Viewfinder Magnification 0.8× (0.5× 35mm equiv.) 0.9× (0.56× 35mm equiv.)
Viewfinder Resolution N/A N/A
Photography features
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
Frames per second 3 fps 5 fps
Minimum Shutter Speed 30 seconds 30 seconds
Maximum Shutter Speed 1/4000 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
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 Rebel XTi
Canon EOS 20D Astrophotography
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 Rebel XTi
Canon EOS 20D Astrophotography
Memory Card Compact Flash
Compact Flash
Connectivity
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
HDMI Output No No
Microphone Port No No
Headphone Port No No
Wireless No No
Remote Control Yes (E3 connector, InfraRed) Yes (N3 connector)
GPS No No
Body & Dimensions
Canon EOS Rebel XTi
Canon EOS 20D Astrophotography
Enviromentally sealed No No
Battery Battery Pack Battery Pack
Battery Details Battery Pack NB-2LH
Battery Pack BP-511A
Battery Life (CIPA) 360 shots 1000 shots
Width 127 mm 144 mm
Height 94 mm 106 mm
Depth 65 mm 72 mm
Weight 556 gram 770 gram