My word, I am shocked at how superb this is! From the thumbnail view it looked just like a photo! There has been some absolutely supreme detail put into the water and the mountains, really well done there! As someone below said, the clouds are the only part that could look a bit more realistic, but other than that this is truly an amazing piece. Well done!
Wow, this is exquisite! You did a great job with all of it! Though as others have said, the clouds do stand out and could use more work. Also the shadows on the land confuse me a bit. Moreso because you have the light spilling out from the left.. I feel there should be more light in other places too. Not sure how to describe it.. XD
I definitely thought this was a photograph until I saw the category you had it submitted under. Great work!
I love the atmosphere you've created here, especially with the lighting and the way the mountains frame the lake. I would say that the clouds could be a bit more textured, but that's not a glaring issue.
Keep up the great work--you definitely have a talent for rendering!