It all depend on how strong your computer is and how you want to use the landscape in the project.
Ofcourse the bigger landscape take more power. There is a possibility to make a big landscape and split in 4 part so you only can use that part you actually need for the specific scene.
I normally use very big landscapes in moderate quality because even in the best quality you have to put gras, trees, rocks and so on in after to get a decent look.
You should see it as something you have to use beneath the other stuff for getting a background color right and so. It will newer get a foto realistisk texture if it stand alone.
I have tried out most of the software one can get like bryce, vue,etc. but when i got a great landscape in vue it just is so big it want fit my needs. And i found Vue vas one of the best software to make landscape in. However, Earth sculpture is amazing because it can do a very great landscape to build on and in a solution iClone can run without problems.
I have attached a picture of a landscape in extreme big size and only put this ship in to lustrate the size of it. The ship is a lot bigger then what usually is used in iclone. So it is BIG -
When you work with Earth Sculpture i suggest you make a landscape and then export in different size to iClone and name them with the export settings so you can se what works best for you and your pc. Its only once, then you know.
Hope that help a little. For iClone i vote 100% for Earth Sculpture.
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