Early Cretaceous (Aptian to Albian), North America
Acrocanthosaurus was a large theropod, with adults measuring nearly 40 feet long. Some fossil footprints in Texas may be attributable to Acrocanthosaurus or a close relative.
The sky is a photo I took; the dinosaur, foreground and most of the vegetation are digital painting. Done in Photoshop CS6 with a Wacom tablet.
[Please don't copy or use without permission, and thanks for viewing!]
And if the sky in the pic is a photo you've done a great job blending it with your digital painting as the pic looks so much like a single painting rather than a painting mixed with a photo.