Apollo Portal will wrongly computes the resolution of the image in the CZS when the Portal CRS is set to EPSG:3857 and when the image to be processed is in a geographic CRS (typically EPSG:4326).
Portal default CRS will be set as EPSG:3857 if user choose to use Open Street Map as background.
The current workaround is to set portal default CRS to EPSG:4326 before CZS any Geographic image.