OECF 20 Chart (following ISO 14524/15739) contrast 10.000:1, 100.000:1, 1.000.000:1
The former OECF chart contains 12 or 20 gray patches in a circular order and three different patterns in the center of the chart. The current version of the OECF chart skips the center patches due to the sometimes occurring stray light. This chart is also offered as YE0264X (D280 format only) where the 20 gray patches are not rasterized as in the standard version of the chart but done with nearly no structure on a very fine grained film.
YE0264 version 2 (V2) uses the same data measurements as the original version, but has a different hardware design. The first version of the YE0264 uses two plates of glass built around the chart film. On occasion we encountered a few problems with stray light and reflections from the glass. Version 2 replaces the glass with a metal frame, which greatly reduces the chance of stray light and reflections.
The standard size for this chart is D280. We also offer size D240 and D240S on request. As these sizes can be used for multiple illumination devices, we want to ensure you are getting the correct size for your device. Please visit our contact page for inquiries.
Principle
Transparent gray scale test chart to determine the OECF, noise, SNR and dynamic range, available in different contrasts.
Features
Type/s of pattern: gray scale, circular arranged (most optical systems are rotationally symmetric so all patches will be affected in the same way by shading)
Values that can be gathered from analysis
• OECF / gamma curve
• dynamic range
• noise
• temporal noise
• visual noise
• SNR
• ISO speed of the camera
