Problems opening a USGS Geotiff

I've downloaded a 64 Mb geotiff from the USGS website. The tiff image opens correctly (all colors and text) with an image viewer. In GM, Global Mapper v16.1.5 (b042115) [64-bit] - REGISTERED, the image opens as a gray image, roughly in the proper map region. It is essentially unusable. Is there an issue with the version of the geotiff? Any suggest work arounds?
Thanks,
Mike
Thanks,
Mike
Comments
Mykle
Hey Mykle,
It is a USGS map by Ed DeWitt et al for the area around Prescott to Verde Valley SI Map 2996. I found a work around by opening the geotiff in GM15 on another machine and exporting a GeoPDF. GM16.1 was able to read the GM15 geoPDF. I think GM16.1 must have a problem reading the geotiff format as it plotted roughly in the right place.
Hooray for GM15!
Hope you are doing well.
Mike
It was not georeferenced, but loaded (took several minutes) and georeferenced without problems.
The downloads folder includes shapefiles that also loaded fine, both geology and basemap zip files.
Interesting area in which we work now and then.
Cheers,
Mykle
Mykle
Cheers,
Mike