That is as true for fiction or non-fiction. The writer has...

That is as true for fiction or non-fiction. The writer has to really know their subject. It is really important to remember that the readers are a lot smarter than the writer. Also, good writing has to do with rewriting. You will never get it right the first time. So you rewrite and rewrite again until you get it right. Until you, and the reader, will be able to visualize what you're writing about.