I started using some production stills as reference (3.bp.blogspot.com/-0bTw9V8RvRU…
), drawing some rough lines to define the areas. Then I used the standard "Hard Round pressure opacity" brush varying the size. Some liquify and resize to fix areas like the head, simmetry, gun size, etc. The background was made on a different layer and merged later. Some gaussian blur for the gun and the background.
I finishing painting the character some day in late November, but abandonend until this month to add a background and make some fixes. You can check the process here: fav.me/d8ibs3v
Total time, maybe 10-12 hours?
It doesn´t look exactly like the original photo, but thats the idea; it has a nice/coherent look on his own where you can appreciate the strokes and an armonic color palette.
I will keep doing some of these to improve my understanding of light and digital brushes...