"The Topo to Raster tool has not been updated for 9.4. Its still the same version of ANUDEM as it is in prior releases." ie 4.5
What a pity, I was hoping for an updated version of ANUDEM, say 5.2, that now uses breaklines and has improved the model in other areas.
I find I have to tile up my topo data to build a good DEM but unfortunately there are a lot of artifacts when that is done.
1. You have to handle split lakes separately to find the level and mask them afterwards.
2. Islands in lakes are not handled, so these have to be put back in.
3. Large features on the edge do not get modelled properly unless you have an enormous cell buffer.
4. Floodplains are very hard to get looking plausible especially if you add stream lines that meander.
5. Every now and again there is a spike in the model caused by some unknown issue in the data.
6. Using a file based parameter list does not cut it because the parameters need to be dynamic to handle a series of tiles.
7. There is a limit to the number of tiles that can be merged, so it has to be done in a series of ever larger builds. Replacing a faulty tile is very difficult because of the complicated merge.
8. The limit command does not work to limit the data processed so I have to clip all participating layers for each tile.
9. Hillshade grids will be one pixel short all around the tile, so they cannot be merged later unless you build oversize tiles and then clip again.
10. Some tiles are too sparse to build, for example small islands off the coast, so the tiles have to be combined into a single non-standard tile, processed and then clipped out.
The process is extremely complex so I have reverted to a series of AML and Workstation that run to completion.
