Fringe stopping
= Fringe stopping
{title2=$V_{\rm stop}=V e^{-i\phi_{\rm ref}}$}
Electronic compensation of the time-dependent reference <geometric delay> multiplies each <complex visibility> by an opposite reference phase. A stationary <point source> at the <phase centre> then has constant corrected phase despite Earth rotation. <antenna> pointing alone does not perform this correction. Off-axis sources retain the relative fringe evolution that encodes their angular offsets.