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Error paper

Rhys Thomas edited this page Feb 8, 2018 · 2 revisions

Aim: Characterise the effect of SEM based distortions on accuracy of strain measurements from DIC

Conditions

  • Material: ??
  • Pattern: One styrene-vapour (~20 nm speckles), one water-vapour (larger)
  • SEM: Magellan\Quanta? Or Magellan for both to keep consistent?

Measurements

  • Two successive images, calculate error values in Exx, Eyy
  • Take image of SEM calibration grid to asses spatial distortion

Variables

  • Magnification -> what mag is best for a given pattern size, is magnification value accurate, does it change in different sessions, is there any spatial distortion
  • Current\Dwell -> what parameters are best to minimise error and distortion
  • Focus -> Go in\out of focus to asses error
  • Brightness\Contrast -> is there an optimal histogram to achieve least noise
  • Stitching -> how does stitching affect the error values