This question has been asked before but I am running into an issue that I could not resolve by looking at previous forms.
I have a DEM that I am attempting to derive the slope from. My coordinate system is a local one, 3TM in this case, and the vertical coordinate system is NAD 1983 (CSRS) [as per the metadata for this layer]. I have attempted to apply a z factor of 0.00001395 and this results in very, very small slope values (0.000056108 at the smallest). While I know the area in question is pretty flat, I know there are areas in the DEM that have a 5% percent slope which I did not get (my highest value was 0.01430756).
I did also attempt to run the tool without a z factor, and this resulted in massive slope values (which lead me to apply a z-factor).
It is highly likely I am missing something very basic so I am open to suggestions.