TransDEM Forum

Hello Roland,

I am unable to do the WMS tutorials for the U.S. as both services are resulting in errors.

1. USGS National Map

http://raster.nationalmap.gov/arcgis/se ... /WMSServer

CONNECT results in message window:

WMS Error Message: "No Error" (????)

process aborts.

2. National Atlas WMS:

I am able to Getmap the route, at various scales/resolutions, but they are always WHITE rectangles.


As a result, I have not been able to acquire the kind of variable-detail geo-referenced raster images for North America that I was able to get with your Mecklenburg-Vorpommen tutorial.

I'm hoping that you might be able to get me back on track.

I just found the answer to the first problem with USGS National Map, and will work on that.

jawais84 Post subject: USGS WMS Error

Thanks!

If you have any thought on the white tiles from National Atlas WMS, I would be very interested.
The one idea I saw listed for this was "try again in a few days" as perhaps it is also a server
issue?

This USGS WMS appears to have been retired. (The next edition of the manual will reflect that change.) Fortunately, there is an alternative option, a map tile service by ESRI with presumably the same data base:
viewtopic.php?p=1832#p1832
If you installed the latest map tile settings (July 2015) in TransDEM, you will already have this provider at your disposal.

The other option is the USGS GeoPDF collection, current and historic. It's much slower because you have to identify and handle every single map sheet but you have full control over timeline and era.

Thank you Sir,

I was able to connect to this server. It seems that the maximum zoom value allowed here is "15", which offers a far less detailed map that was available for your earlier tutorials with German map servers. At higher resolution, the data is unavailable. Is it possible that there is not currently a way to use TranzDEM for detailed tracing of U.S. rail routes? To be direct, do you think detailed data is becoming less available here, or is there a possibility that it is a matter of research to find where it has migrated?

It also seems that orthophotos offer the best information for details like buildings, trees and other features. Do you have any thoughts on sources for batch downloading photographs, or is Google Earth the best current solution? From the tutorials that I found, Google Earth was being done on an image by image basis. Did that predate the option for trace route in Getmap or do the two methods offer different capabilities? And finally, there any options for higher resolution imagery than Google Earth may allow based on the 1 pixel scale limitation?

Lastly, you may already know this, but I stumbled onto a new USGS server for DEMs.

USGS TNM Download (v1.0)
http://viewer.nationalmap.gov/basic/#productGroupSearch

It offers interactive real-time selection and download with a simple UI.
I just selected "Elevation Products" and checked 3 boxes in the list:

1/3 arc-second DEM (or 1 arc-second)
ArcGrid
1x1 degree,

(I hope that is all correct)

Thanks again.

The map here is the standard USGS 1:24k topo map. The edition on offer is rather old, it was made public domain quite a few years ago, I think, so railroad-wise it shows many fallen flags. This map may not be granular enough for high-density built-up areas but should be more than enough out there in the country. Once you look closer you will be surprised how much detail these maps actually carry. And 1:24k is the largest scale that can be painted with TransDEM ground textures without becoming blurry (5 m baseboards required).

1:24k is the largest scale produced by USGS as far as I know. The current series and the entire historic collection are delivered in GeoPDF format but need do be downloaded and processed one by one.

Try some of the other map tile providers. Open Street Map usually has the best railroad data, while Google is struggling to catch up.

Google and Bing (the latter under its original name "Virtual Earth" in TransDEM) also offer ortho-images as map tiles, so that's the quickest way to acquire a series of clippings. However, Google will cut the connection after a while. It's their policy. You would get a few more tiles, at the price of data mining, with a Google account, but TransDEM does not support this.

It's called UTM tiles in TransDEM. These are large scenery objects which serve as mere texture carriers. They come in two sizes, 1000m and 500m, and can be created as 2D (fast, flat surface) or 3D (slower to make, terra-formed surface). With a 500 m UTM tile and a 4096 pixel texture, 1 pixel equals about 4 inch.

No, I had not seen this new interface of The National Map Viewer, but it's definitely quicker than the old one.

Two more remarks, slightly offtopic:

1. Take a USGS 1/3 arc sec DEM, create an overlay with the USGS 1:24k raster topo map, turn on DEM shading in TransDEM, zoom in and look for transport arteries, highways or railroad right-of-way or even smaller structures, like sewage ponds. Adjust transparency and shading intensity for best viewing results. You will be amazed.
   
2. TransDEM is rather efficient and quick in generating huge Trainz route templates, particularly if you use the automatic map/image downloading features. But do not underestimate the amount of work remaining, after you open the new template in Trainz Surveyor the first time, before you get a presentable or even a usable route.