1/3 Arc or 1/9?

[SithMurcielago]

As my never say never attitude, I'm going to try the Redem again. First I'm drawing my planned path for my route (Auto Train), and I'm wondering if it is bette to use tiles that are 1/3 Arc or 1/9?


Your View?

[Toripony]

1/9 is more accurate but only available in limited areas of the U.S. When I run my data download, I select both, download both, run the 1/3 first, then run the 1/9 into a different folder. Then collect the 1/9 tile files that actual have data in them and put them into the main folder, overwriting any 1/3 tile files. The downside of this is it can leave you with more DEM "holes" than just using pure 1/3 data. Trying to do far north regions (bad angle for satellite photography from above the equator) get so full of holes that I gave up using any 1/9 data.
The C&O Alleghany is built from 1/9 data on the WV side of the border and 1/3 data on the VA side.

Tori

[SithMurcielago]

Interesting, My Route Starts in VA, and ends in FL. Would you considered those areas 1/9 worthy? I want the best results from that data as possible. I will do what you Do and download both and best them out to see which one yields the best results.

[MadMike1024]

Interesting, My Route Starts in VA, and ends in FL. Would you considered those areas 1/9 worthy? I want the best results from that data as possible. I will do what you Do and download both and best them out to see which one yields the best results.

I'd look at the map to see what coverage is available. It will show you whether or not the 1/9th is there. If it is available, use the 1/9th because it makes the roadbeds and streets show a lot better.

MM