I recently saw the newest episode of Planet Dinosaur (which is pretty much amazing) which discussed the newer discoveries of feathered dinosaurs.
As expected, the majority of the reconstructions were very conservative, giving the dinosaurs a simple downy coat. However, some such as Microraptor had prominent flight feathers on their arms, legs and tail.
Now look at the wings.
I also noticed this in the opposite-polarity documentary "The Future Is Wild" with the 'Blue wind-runner' - A large, blue, goose-like bird that lives on high mountain plateaus.
Here's the problem:
Look where the body meets the wing - the feathers just sort of stop. What these models ignore is that bird wings aren't just skinny arms with feathers stabbed in.
Bird arms are actually webbed
This webbing adds to the surface area of the wing and creates the smooth line from wing surface to body surface.
It only seems to be the lower budget CG documentaries that have this flaw, but they make the same mistakes.
Hair has already reached near-perfection in CG to the point where it's available in most packages, but feathers are different. They're much bigger, discrete structures that have such a vast variation that an easy paint-method would be initially difficult.
Fentil creatures are mostly bald, so issues like these are luckily avoidable. The closest thing to hair is the down found on Pouchbacks (top) and Loopers.
Shankbats (flying Fentil vertebrates related to cloverheads) have main wings similar to those of birds, but as they lack feathers, the webbing is more extreme.
Shankbats probably wont feature much in the CG documentary, but I'm glad that they have a newer, solid design.