Figure 11-17 Gain Curve Adjusted Dgs; Registration Level Adjustment - Olympus EPOCH 650 User Manual

DMTA-10055-01EN, Rev. A, February 2015
11.3.5

Registration Level Adjustment

The registration level of the DGS/AVG curve defines the height of the main curve. The
curve height represents the amplitude from a flat-bottom hole with a diameter of the
registration level at different depths. This is usually equal to the critical flaw size for
the application. The EPOCH 650 allows you to adjust this registration level during a
live inspection.
This curve-height adjustment is possible because the DGS/AVG curves are
calculated based on a captured reference-reflector and mathematical probe data.
This allows the EPOCH 650 to plot the attenuation curve (in steel) for a particular
size reflector without having to acquire individual data points, as is required in a
DAC/TCG setup. This is one of the key advantages of the DGS/AVG sizing
technique over the DAC/TCG sizing technique.
248 Chapter 11

Figure 11-17 Gain curve adjusted DGS