I am trying to create a set of 2ft contour lines in ArcGIS Pro and I have a set of 6 or so .tiff files. I have mosaiced them together into 1 .tiff file. I tried running the contour analysis tool on the file and ended up with an impossibly large contour dataset that doesn't look right at all. Do I need to use a different file format? I've used a DEM in the past and that worked just fine, but there don't seem to be DEMs available in the area I'm working in. I don't know how to work with .tiff files, so I'm not sure just what else to do with it.