I think nature images are hard because we have a very good idea of what nature looks like. We see it all around us and our brain notices immediately when things don't look right. Even if we can't put our finger on what's wrong exactly. The biggest problem with landscapes is that most people want to make it much more romantic then most landscapes are in real life. You have to find a balance between realism and very strong emotional aspects of the landscape. This is easiest to achieve by making a mainly realistic scene in bryce to begin with and then using postwork to add details and increase the aspects of the image that make it look so nice and romantic.

(_/)
(='.'=)
(")(")This is Bunny. Copy and paste bunny into your signature to help him gain world domination.