Aster DEM

[Darpor]

Evening fellas.

As you will know, we now have the option of using Aster DEM within routes as an alternative to SRTM data.

I was wondering if anyone had actually used it yet and tried to package up a route, even a small test route without scenery. This is because I have just tried myself, and although I hadn't raised a great deal of terrain, only 8 miles or so in each direction, this small test route with little scenery packages up to 57.8mb! Looking in the terrain folder, it had generated 1158 .bin files, all substantially bigger than anything I have seen previously.

My questions are:

* Is it generating more tiles than I imagined, even though it only took a few seconds to travel over the world editor to the "cliff" where the generated terrain ended?
* Is the Package Manager not able to compress this terrain as much as SRTM?
* Is this type of terrain creation simply too expensive in terms of file size?

[charlie99]

Something I noted when using aster data alongside SRTM data was that it was in general about 40m lower than the SRTM, therefore pretty much useless for me.

[longbow]

Terrain bin files carry elevation data for each grid point in a single tile and are I think always 65k in size. Using a different DEM source should not change that; the terrain grid size is as before so you'll still have the same number of data points. Thus it seems that you have inadvertently DEMed a very large area.

ASTER data has been tried in RW. Early opinions were mixed. It is higher resolution than SRTM with better coverage but early data had a lot of holes and other glitches in it. Perhaps this has been improved since. For the UK the converted OS Panorama DEM data available in the library is probably still the best option.

[Darpor]

Terrain bin files carry elevation data for each grid point in a single tile and are I think always 65k in size. Using a different DEM source should not change that; the terrain grid size is as before so you'll still have the same number of data points. Thus it seems that you have inadvertently DEMed a very large area.

ASTER data has been tried in RW. Early opinions were mixed. It is higher resolution than SRTM with better coverage but early data had a lot of holes and other glitches in it. Perhaps this has been improved since. For the UK the converted OS Panorama DEM data available in the library is probably still the best option.

After further tests, you are right, 65k no matter what DEM source and most likely I have DEM'd far too much, mostly un-needed terrain.

The OS Panorama is what I would normally use and I was quite happy with it. I just tried to create another route using the same template, then copied everything over apart from the .xml and scenery folder. All is present of course, but the DEM wasnt much different at all, certainly not with a height difference that Charlie is experiencing.

Lesson learned I guess, just proceed with 3x3 spreads as and when needed.

[charlie99]

The DEM I was using was in the high alps, which probably explains the heights.

[alexedwin]

It could be a lot better soon.
http://forums.uktrainsim.com/viewtopic. ... 4&t=119099

[paulz6]

Raw Aster DEM is about as smooth as baby wipe. I would rather leave stains on it.