it is possible to accurately recreate Earth in Terragen 3?

[bigben]

Yes, your clouds are coming along very nicely.  I'm still downloading data to patch together. Half way through the tiles for GMTED2010 when I discovered how crappy the Himalayas are..  It's beeen a few years since I put up with Earth Explorer's "thou shall have only 4 simultaneous connections and thou shall not automatically harvest data"  It's a good thing nerds have a lot of patience 

[Ariel DK]

Well, I'm also having a stupid problem with a dataset too
in my case it is nothing less than the dataset NASA earth 86k color + topo
I have already downloaded the entire southern hemisphere, but I can not load other plates with Chrome
I increased my speed internet, but happen exactly the same: the textures never load

[Ariel DK]

Another update
I conformed with this but there are still areas where clouds seem to behave oddly
300km above Sumatra

[bigben]

Well, I'm also having a stupid problem with a dataset too
in my case it is nothing less than the dataset NASA earth 86k color + topo
I have already downloaded the entire southern hemisphere, but I can not load other plates with Chrome
I increased my speed internet, but happen exactly the same: the textures never load

I generally use Firefox with the Download Them All extension. It gets the files in multiple segments at the same time which helps speed things up and it's pretty good at resuming stalled downloads.

I'd suggest using the images without topo as they have shading which can look quite odd closer up if the sun position doesn't match it's shadows. Send me a PM with your email and I'll send you mine.

[bigben]

And on the masking side of things.... I'd suggest using a colour adjust shader after each key component of your mask. I find it much easier to fine tune distribution masks with this.  And as clouds take a while to render, use the same mask on a surface shader. It also makes it a little easier to see if a problem is located in the cloud settings or the mask.

[Ariel DK]

Thanks, use surface shader is a good advice bigben, I'll try it later
for now I'm focused on creating clouds with a "semi-procedural" aspect
with an alpha image (to restrict the clouds to certain areas),with a little noise variation.
the best of this method is that the resolution of the image should not be at all high

[Ariel DK]

I bring good news about masking clouds
I have found with enough research on internet,
there are satellite images calls AMO.
constantly shows the Color of the Earth and clouds
in total there are at least 2 million of these images, each with a resolution of 6k or less
although the frames are different days and years, they can be easily edited and combined
into potoshop, to create the first map of clouds at 100K resolution!!!
Unfortunately, I don't know if the best solution
to a manageable model of the Earth 

[bigben]

I've seen a few low res texture maps for clouds that were "artistic composites".  They produced a few different versions by patching in local sections, e.g. A version with relatively clear skies and another version with some of the gaps filled with cyclones.  As long as you keep the latitude for an image section the same, you can move it east/west to suit.

[Ariel DK]

I've seen a few low res texture maps for clouds that were "artistic composites".

Again you are in the correct Bigben
but this technique should expect
because I've gotten amazing results
using only "semi-procedural" layered clouds
pd: ignore the resolution of the textures, I'm downloading new data

[bigben]

The last time I played around with cloud masks was with Hurricane Katrina. One of the approaches I used there was to create a mask image in ImageJ for the small dense cumulus formations by filtering by particle size.  By playing around with contrast and particle size you can pull out a few of the different cloud types.  If you can get your hands on images at multiple wavelegths you can mix and match to get some other combinations. I think I'll be aiming for 3 cloud masks combined in an RGB file (just to keep the file count down) but I'll see when I get there.

I also have a water mask for continent outlines. A blurred version of this could be used to mask by distance from the coast which might be useful.

[Ariel DK]

thanks again, but for now I'm just focused
in the atmosphere settings
However, I foresee a complication when I it begins
to load large data sets, because I have only 8GB RAM
will this be enough??

[Ariel DK]

more news..
who is this guy?? 
http://www.turbosquid.com/3d-models/earth-clouds-256k-x/828437

[bobbystahr]

more news..
who is this guy?? 
http://www.turbosquid.com/3d-models/earth-clouds-256k-x/828437

at $1300.00 approx. for the model; no one I'm ever likely to know, hee hee hee

[Oshyan]

I don't even see any mention of Displacement Maps. Without that a million poly sphere isn't going to have nearly enough detail for any decent height representation, so it becomes just a flat Earth with nice textures. I'm not certain of the source of his data, but if I recall correctly Blue Marble has max resolution data that might stitch together to be that resolution or higher. There are some errors or visual artifacts in some of his example images too. Wonder if anyone is paying that much... eek.

- Oshyan

[bigben]

Blue Marble stitches together to 85k. The resolution on these images looks about right for the 256K mark, but it's not as clean as Blue Marble. Significant banding between satellite passes in the Amazon example.
Here's a comparison with one of the Blue Marble JPEGs (coincidentally a 1:1 crop)

...and yes, no sign of any terrain. "The best results near the surface ever seen" if you call 50km near