Hi, when I get a displacement map, “Colour Manipulation” sets boundaries automatically. So it should be, or should you establish the boundaries yourself?
SNAP automatically scales color palettes over only 95% of the raster values (the lower 1% and the upper 4% are left out) so that contrasts are enhanced. Extreme outliers could lead to pale images. If not all values of interest are included you can click on the 100% button and have the colors scaled over the total extrema of your raster. But it is very likely that InSAR produces some wrong values at the edges so not all can be trusted and I’d personally stick to 95%.
Maybe this also clarifies some more:
both are technically correct, the raster values do not change with different colour stretching.
But some patterns in the 100% image are probably unusable.