I used ArcMap to georeference a batch of scanned topo maps and created a mosaic of the rasters. I would like to export this mosaic as an image and add it to Google Earth as an overlay.
I have attempted to save the mosaic in PNG or JPEG format, but am having issues. I've used "Copy Raster," "Export Mosaic Dataset Items," and right-clicking on the mosaic layer to select "Export Data."
The results are a bunch of files that open as blank, black images.
I am looking for any advice regarding this process.
Alternatively to exporting your own, there are several other options. There are already several good KML services for USGS Topo Maps, if you wanted to go that route(see attached). Also you can download historic topos as kmz files from the USGS HIstoric Topo Viewer.
First, do you know about ArcGIS Earth? It is free software that understands ArcGIS data formats and structures and may provide a great alternative. ArcGIS Earth
However, to the question of exporting images, look for the "NoData" value in the export UI. I am guessing when you export you are accepting the default of "Nodata = 256", and that results in promoting 8 bit data to 16 bits (which is undesirable; enter 0 for nodata instead).
There are reasons for why 256 is offered as default that I won't take time to explain. but if you put 8 bits of data into a 16 bit format, it will often appear black even though the data values are there.
I only have a moment for a brief reply. If this isn't clear enough let me know