Problem: Some exports with 8-bit palette may result in a 4-bit image.
When exporting a map from ArcMap and choosing the 8-bit paletted, 256 color option, the resultant export only contains a 4-bit, 16-color color map.
If there are less than 16 color values in the map, the resultant export contains 16 color values to minimize file size.
Solution or Workaround
This is a known and expected behavior.
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