I just found those pics during a google image search. They were high enough quality to where I could use them. Not sure what comic they came from. Sorry.
I did this one using an animation cel of the sentinel (same cel used on cover 3) and placed it over the original image and photochopped it together. Turned out pretty cool. Also, none of pics are screencaps except for the three pics on the back covers. They are all animation cels.
