Is there a Limit on the Tightness of Contour Lines for a DEM (resolution 1/3 arc sec)?

[Cathina_Gunn_de_Rosas]

Howdy,

I have a DEM with a resolution of 1/3 arc seconds. I would like very tight contour lines, but am getting errors when I try to do something as fine as "1" as the contour spacing value. Is this due to processing power or because the resolution of the file itself does not allow it?

I guess I'm assuming ArcMap would simply interpolate between real values, but I wanted to be sure before I blamed it on the computer.

[VinceAngelo]

What exact errors are you getting?  A 1-foot contour interval is better suited to an engineering survey over an acre than something of the scale you seem to require.  Are you applying a filter to your DEM to avoid jagged artifacts in the contours?

- V

[SepheFox]

What is the extent of your data, Cathina? How large of a geographic area does it cover?

[SteveLynch]

What is the spatial extent of the data? The data appears to be in a geographic coordinate system, have you changed the output coordinates in the environment to a projected coordinate system? What is the elevation range?

A small contour interval does not mean that you’ll necessarily get accurate contours. ☺

Also, for testing purposes, zoom to a smaller extent and in the environment set the processing extent to display and then run the Contour tool.

-Steve

[Cathina_Gunn_de_Rosas]

Thank you everyone for your input.

The full area is ~1 degree lat by 1 degree long. I actually figured out a more accurate and efficient way to get what I needed but this advice will be helpful in the future. I will run a test on a smaller area to see if that is the problem.