I'm using with arcgis enterprise portal some DTMs published as Imagery Service, and I see some strange error in the legend and in the map rendering.
When I use configuration like this one:
and, generally speaking, when I use "continuous" color ramps (from dark blue to light blue, from dark gray to light gray, from dark red to light red, and so on) the visualization works as expected, but if I use other color ramps that not use the same color, like this one:
I see something strange in the legend and in the map:
second "zoom out":
third "zoom out":
Basically, the legend and the map it's ok at start, then becomes broken at first zoom in (or zoom out), then becomes ok at the next zoom in/out, and so on.
Please consider that when status of the legend is maintained when I pan the map, only when I zoom I see the problem.
I tested with ArcGIS Enterprise 10.8.1 with patches from the march 2021 (not April 2021), using the integrated map viewer (but the same problem appears using developer app builder 2.18 and the integrated map builder).
Please note too that if I configure the raster dynamic rendering using "minimum and maximum" (instead of percent clip) the problem still remains.
Actually the steps to reproduce the problem are quite simple:
Hope to be helpful