What each control does

wipe

the original on one side of the gold seam, the model's output on the other. Drag the seam itself.

fade

dissolves one into the other, for spotting what moved rather than what vanished.

difference

subtracts the two images. Black means they are identical; anything that glows is a pixel the model changed.

amplify

multiplies that difference so changes too small to see become visible. Difference mode only — a magnifying glass, not a measurement.

blink

alternates the two layers every 450 ms. The fastest way an eye catches something that shifted position.

re-fit

back to the starting frame.

wheel / drag

zoom at the cursor; drag to pan once you are zoomed in. Real pixels, not interpolation.

space

hold to see the original alone.