This standard is based on the but there are some improvements: - beside film also digital technique is allowed (CR and DDAs or radioscopic detector) - recommends to use a proper E2002 Platinium duplex wire as edge - takes the influence of SNR into account and - gives a formula for optimal magnification M: . . . . . . . . . . Moptimal = 1 + 1.1*SNR(P/ Soptimal) . . . . . . . . . . with S = focal spot size; P = pixelsize; SNR = unattenuated Signal-to-Noise ratio outside the object - calculates the unsharpness "Klassens-conform" from 2* (50% -> 84%)
- uses the correct formula for calculation of the focal spot size
- provides a statement on the repeatability
If you have the choice - use the ASTM version for measurement of the effective focal spot size of your µ-focus tube.
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