There are also a small texture patches and text blocks on the left and right at the foot of the chart which can be used for visual assessment of image quality. It is especially useful when adjusting a ZEISS CP. Below the test patterns is a line which is exactly 100mm long that can be used for calibration as described later. ZEISS Siemens Star Test Chart The ZEISS Siemens Star Test Chart is a professional lens chart that has been used for decades to set the back focus on lenses used on individual cameras. I place these files into the public domain and make no claims for their accuracy or ability to allow a camera to focus on them. Within the resolution patterns on each side is a Siemens star pattern. It consists of a large Siemens star in the center an four smaller ones positioned in the corners of. The links are:įor the Illustrator "source" file (1.1Mb) Back Focus Test Chart (36 cycles with corner stars). Any photograph of the chart would contain much stronger artifacts. The target should print onto an 8.5x11 sheet of paper. The superior science behind ZEISS SmartLife Lenses. At least this is how this kind of test chart is called in Germany ) The artefacts in the middle of the chart are Moiré artifacts caused by resizing the original chart. I've made available a similar target in Adobe Illustrator (CS6) and in PDF format. I believe those charts are expensive and/or copyrighted. 2 ZEISS Primostar 3 Your robust yet compact microscope for digital teaching and routine lab work. In the video clip, the author refers to a "Siemens Star" chart. 0 Comments Another unit is ' cycles/pixel' which is 0.5 when LW/PH equals the vertical number of pixels. With all the concern about D800 focusing, I thought I would contribute to the "war effort" by making a focus target similar to the one referred in the blog posting at
It is much easier to tell if the text is blur or sharp than some random patterns.
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