Time Gain Compensation


Time gain compensation (TGC) may be a set of sliders, or may simply be a near and far button. The facility allows different parts of the image to be ‘brightened’ or ‘darkened’. This is achieved either by a series of paddles or knobs that allow different depths. (as the time of return of the signals, is directly related to depth as represented on the screen.) For simplicity, set it at mid range and leave it. Then use the main gain knob to adjust brightness.

This is most simply thought of as altering the ‘brightness’ at different levels to either dim or lighten parts of the image.

Care must be taken so as not to overuse this function, as it can cause artefacts that can be mistaken for fluid/sludge etc.