Testing procedure

Lens testing procedure

1. Prepare the test chart:

There are many ways to prepare a test chart. Here are two of them: Examples:

Simplest chart generated with Quick MTF
The subject is a very simple test chart created with Quick MTF with the angle of 0 degrees and rotated 5 degrees to the right. Unfortunately, there are no slanted edges in the corners, suitable for testing purposes.
  Quick MTF lens quality test
The subject is made of four simple test charts.

ISO 12233 chart
The ISO 12233 chart contains a lot of areas suitable for testing purposes.
  Tilted USAF 1951 chart
The USAF 1951 chart may be tilted and used as a subject.

You may think of many ways to create a test chart of any size and content. Some devices, such as a microscope or night-vision equipment, may require tiny or unusual test charts. The general rule is that the image made using a test chart must contain slanted edges in the regions to be analyzed. The edges must be of high enough contrast and sharpness, because the results must only depend on the parameters of the device being tested.

2. Provide adequate lighting:

Lighting scheme

3. Take shots:

 

Watch video about Quick MTF usage.
Out of focus blur calculator - evaluate influence of focusing mistakes on testing results.

 

Links:
ISO 12233 Test Chart - contains a printable PDF version and several links for buying a real ISO 12233 chart.
I3A/ISO Resolution Test Chart and USAF Hi-Resolution Target 2'' at Edmund optics.