High!

I just looked through the postings of the last months (I admit, I'm in
quite a delay in keeping up with recent activities here!) - and came
upon Christoph Hormann's magnificent Earth renderings of April 1 made
with the high-res textures from
http://visibleearth.nasa.gov/cgi-bin/viewrecord?11612 (Blue Marble)! I
haven't seen the Himalaya picture yet, but the Italy/Greece close-up is
truly awesome, without any vertical exaggeration!

When I browsed the Blue Marble pages, I didn't see any download link to
the full-res (43200 by 21600 pixels) map, it said "available on request"
- did you order the CD by mail, Christoph? So for my Afghanistan
project, I had to content myself with the 8192 by 4096 version, i. e.
about 5 kms/pixel. I blew the area around .af up to 1 km/pixel and then
cut out the portion exactly (as exact as possible, I had to do this by
guessing) corresponding to my 1 km/pixel Afghanistan heightfield.

After that, I tweaked brightness and contrast with IrfanView, as the
original texture map looked too dark and too saturated in the rendering.

As my scenes, 19 altogether, are viewed from aerial (2.000 to 20.000
metres) or even "pedestrian" rather than orbital perspective, I still
exaggerate the relief by a factor of 2 to work out the terrain features
better at this still low horizontal resolution of the heightfield.

I also rendered a non-exaggerated orbital overview with low illumination
angle (also attached here), but the close-up scenes done this way
disappointed me because of their ugly angular shadows... what I need is
an Afghanistan heightfield with a higher resolution - 200 or 100 m/pixel
would be fine, perhaps also 16 rather than 8 bit! Is there any legal way
to obtain such a large, accurate heightfield, or do I have to do it
myself from painstakingly pixeling topographic maps (at my current
working speed, I would be ready around 2750!)?

Here a few examples - 1 unit=1 metre!

The first image (Afghanistan00_morning_sun) shows the entire country
from altitude of 2,000 kms looking down vertically with illumination
coming from low ESE - terrain is not vertically exaggerated!

In all the following scenes, the terrain is exaggerated by a factor of
2, all features appear twice as high as in reality, camera positions are
also adjusted.

In the second image (Afghanistan09) you stand somewhere in the center of
Kabul (eyes 1.7 m above ground), looking NW towards Paghman Range (4,600
metres high, ground is at about 1,800 metres). The 2,100-metre hill to
the left is Koh-e Asmai, in reality crossed by Kabul's ancient town
wall.

For comparison, I also added the non-exaggerated version with low-angle
illumination (Afghanistan09_morning_sun) - the only image from this
series which halfways satisfied me.

Afghanistan11 is a panoramic view from the highest peak of Paghman Range
to SSE over the Kabul basin, Koh-e Safi (3,200 m, to the left), Spin
Ghar (middle) with OBL's famous-infamous Tora Bora hideaway, Khyber Pass
and, to the horizon, the green Indus plain.

On Afghanistan18 you see Mt. Noshaq (7,485 m), Afghanistan's highest
mountain, seen from the summit of nearby, but Pakistani Tirich Mir
(7,708 m), in the background the Pamir highlands and the upper Amu Darya
(Pyandsh) valley.

There so much more work to be done...

...see you in Khyberspace!

Yadgar

Now playing: Tandem (Tangerine Dream)

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Attachments:
Download 'afghanistan11.jpg' (22 KB) Download 'afghanistan09.jpg' (13 KB) Download 'afghanistan09_morning_sun.jpg' (13 KB) Download 'afghanistan00_morning_sun.jpg' (87 KB) Download 'afghanistan18.jpg' (25 KB)

Preview of image 'afghanistan11.jpg'

Preview of image 'afghanistan09.jpg'

Preview of image 'afghanistan09_morning_sun.jpg'

Preview of image 'afghanistan00_morning_sun.jpg'

Preview of image 'afghanistan18.jpg'

> 
> [...]
> 
> When I browsed the Blue Marble pages, I didn't see any download link to
> the full-res (43200 by 21600 pixels) map, it said "available on request"
> - did you order the CD by mail, Christoph?

As i have already said elsewhere the full resolution data files used to be
availabe on an ftp server that was linked from:

http://earthobservatory.nasa.gov/Newsroom/BlueMarble/

The URL is:

ftp://gloria2-f.gsfc.nasa.gov/pub/stockli/

But that ftp does at least at the moment seem unavailable.  There is
another ftp with various data files:

ftp://visibleearth.nasa.gov/pub/EARTHVIZ/

but i don't know what they contain.

Christoph

-- 
POV-Ray tutorials, include files, Sim-POV,
HCR-Edit and more: http://www.tu-bs.de/~y0013390/
Last updated 28 Feb. 2003 _____./\/^>_*_<^\/\.______

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High!

Christoph Hormann schrieb:

> There is
> another ftp with various data files:
>
> ftp://visibleearth.nasa.gov/pub/EARTHVIZ/
>
> but i don't know what they contain.

Possible there are those huge texture files, I spotted several entries over
400 MB... but then also this:

"If not authorized to access this resource, disconnect now.
Unauthorized use of, or access to this resource may subject you to
disciplinary action or criminal prosecution.

By accessing and using this resource, you are consenting to
monitoring, keystroke recording, or auditing."

No, I just don't want to be on the CIA death list just for my interest in
hi-res surface textures of Afghanistan!

See you in Khyberspace!

Yadgar

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