| Support this site by shopping via these links |
|
|
|
Canon PowerShot G7 wide-angle geometry comparison
 |
|
To measure and compare the Canon PowerShot G7's
geometric distortion we photographed a test chart consisting of a grid pattern,
using it and a number of rival models.
Here are the results for each camera with their built-in or kit lenses at their
widest focal length; where possible, the aperture was closed.
The images were analysed with Imatest using 5th Order line calculation and
the full areas presented here at a reduced resolution.
|
7.4-44.4mm at 7.4mm
Distortion: 3.34% barrel |
| |
| The image above was taken with the Canon PowerShot G7 zoomed-out to 7.4mm.
Barrel distortion was measured at 3.34% which while virtually identical to the EOS 400D / XTi's kit lens, is measurably higher than both the PowerShot A640 and Panasonic DMC-FZ50. |
Canon PowerShot A640 |
|
Canon 400D / XTi
(using EF-S 18-55mm) |
|
Panasonic DMC-FZ50 |
|
|
|
|
|
7.3-29.2mm at 7.3mm
Distortion: 2.48% barrel |
|
18-55mm EF-S at 18mm
Distortion: 3.35% barrel |
|
7.4-88.8mm at 7.4mm
Distortion: 2.56% barrel |
Canon PowerShot G7 telephoto geometry comparison
 |
|
To measure and compare the Canon PowerShot G7's
geometric distortion we photographed a test chart consisting of a grid pattern,
using it and a number of rival models.
Here are the results for each camera with their built-in or kit lenses at their
longest focal length; where possible, the aperture was closed.
The images were analysed with Imatest using 5th Order line calculation and
the full areas presented here at a reduced resolution.
|
7.4-44.4mm at 44.4mm f5.6
Distortion: 0.28% pincushion |
| |
| The image above was taken with the Canon PowerShot G7 zoomed-in to 44.4mm.
Pincushion distortion was measured at 0.28% which is the best result of the cameras shown here, albeit not by a huge degree. |
Canon PowerShot A640 |
|
Canon 400D / XTi
(using EF-S 18-55mm) |
|
Panasonic DMC-FZ50 |
|
|
|
|
|
7.3-29.2mm at 29.2mm
Distortion: 0.35% pincushion |
|
18-55mm EF-S at 55mm
Distortion: 0.39% pincushion |
|
7.4-88.8mm at 88.8mm
Distortion: 0.34% barrel |
|
