Eye in the sky

JohnH wrote:
Pat Thronson wrote:
Hi all,
Here is a nice piece of software you might need/enjoy.

Cute, but Nasa Worldwind shows much more detail.

I've downloaded Worldwind, but was unable to see the detail that
everyone was boasting about. I even went to the USGS maps that the
f.a.q. described as 'the best', but still, I couldn't get as much
detail as the google maps. Any hints, tips??

"Mitch" wrote in message
ups.com...
Cute, but Nasa Worldwind shows much more detail.

I've downloaded Worldwind, but was unable to see the detail that
everyone was boasting about. I even went to the USGS maps that the
f.a.q. described as 'the best', but still, I couldn't get as much
detail as the google maps. Any hints, tips??

In theory, the USGS images are the same (that is, the data should be
identical) that you can get on terraserver-usa.com, and I believe similar to
that available on Google (acquired with the Keyhole technology).

However, my experience is similar to yours. I never saw World Wind download
as detailed an image as the USGS data actually provides at those other
sources. I've only been using World Wind recently, and in writing this
post, I found a reference on their web site that indicates they are aware
that the USGS images aren't up to snuff. Read on, or just skip most of this
post and scan down to the bottom for the specific reference.

In my personal situation, I think it's likely I was running into server
bandwidth issues. For sure, I had other situations in which it either took
a very long time for the detail to fill in, or I just never got more
detailed images at all. I haven't figured out a way to get World Wind to
display a connection and/or download status, so it's hard to diagnose issues
like that. But I know that I came back later and the exact same view showed
more detail.

Something else to keep in mind is that the most detailed USGS data are the
USGS Urban Areas images, and these are not available for the entire US. Of
course, if you can get them on TerraServer, you should be able to get them
on World Wind. Just make sure you're comparing apples to apples.

You can download specific data to stick in your cache directory for World
Wind he http://www.worldwinddata.com/ Unfortunately, the available data
does not appear to include the USGS layers.

Given the large size of the total data used (almost 5 terabytes), you're
pretty much stuck relying on not only your own Internet bandwidth, but that
of the server hosting the data as well. There is detailed information about
using the USGS layer he
http://www.worldwindcentral.com/wiki...he_USGS_Layers Note that the
download times described are on the order of 10 minutes per layer, more or
less depending on your connection speed (and of course, how many other
people are accessing the server at the same time). This is a lot more time
than I bothered to give World Wind...perhaps if I'd been more patient, I
would have gotten the imagery I was hoping for.

Looking at that page again, I just noticed this at the end:
"NOTE: There is currently(March 9, 2005) an issue where the resolution of
the USGS Urban Area Ortho images available through World Wind v1.3 is not as
good as is available from the Terraserver website, or even what was
available using World Wind v1.2, and this issue is being investigated."

I'd say based on that quote, no amount of patience will result in you
getting the full USGS data. They've known about it for a while...I
don't know how to find out how long it will take them to fix it.

Pete