I've created contour lines every 5 meters from a grid DEM with 5x5 meter of resolution. But strangely I've obtained that the contour lines are segmented and rich of lines that goes up and down, especially in the plains areas.
I've then used a focal statistic to smooth the DEM and I've obtained a very good result in term of aesthetic; but is preferable to non alter excessively the original data.
Some suggestions or ideas on what is the problem?!