Lens Testing - 09/03/2012

Task:

The class will divide into groups, each group will assist each other in working through the lens test task below and blog each of your findings/results of at least two lens tests by Week 5.

The task: Testing Two Lenses (or zoom settings)

• Set up the targets on an appropriate wall
• Set up the Tungsten lights as per the diagram
• Ensure that the tripod is level
• Ensure that the camera is level on all planes
• Take images at all apertures to find the one that is sharpest
• Please note that this task is also designed to find other lens aberrations, how many can you find in your lens/es?
• Ensure this info is included along with images of your worst and best aperture.

The lens that i have decided to test is my canon EFS- 18-55mm, here are the results:

 

 

 

 

Exposure: 1/25 sec @ f5.6

Focal Length: 55mm
ISO 100
Lens: 18-55mm

Camera: Canon 60D

Chromatic aberration: blue fringing

 

 

 

Exposure: 1/13 sec @ f8

Focal Length: 55mm
ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic aberration: slight blue fringing.

 

 

 

Exposure: 1/16 sec @ f11

Focal Length: 55mm
ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic aberration: minor blue fringing on outer edge of image.

 

 

Exposure: 0.3 sec @ f16

Focal Length: 55mm
ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic aberration: none

 

Exposure: 0.8 @ f22

Focal Length: 55mm
ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic aberration: none

 

 

Exposure: 1/50 sec @ f4

Focal Length: 18mm

ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic Aberration: pincusion distortion and green and red fringing

 

 

 

Exposure: 1/30 sec @ f5.6

Focal Length: 18mm

ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic Aberration: pincusion distortion and green and red fringing

 

 

Exposure: 1/15 sec @ f8

Focal Length: 18mm

ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic Aberration: pincusion distortion and green and red fringing (only around the edges of the image).

 

 

Exposure: 1/6 sec @ f11

Focal Length: 18mm

ISO 100
Lens: 18-55mm

Camera: Canon 60D

 

Chromatic Aberration: pincusion distortion and green and red fringing (only on the outer edge of image).

 

 

After looking at the results shown above, the images determine that the highest quality point of the lens is at focal length 55mm and at an aperture between f16 and f22. At this pointthe lens has no chromatic aberrations or distortions. In the 18mm range the lens has continuous pincusion distortion, due to the lens being at a wide angle.