Several versions of the comparison between the alleged Sasquatch female in the Patterson-Gimlin film footage and an ordinary human male in a movie gorilla costume: the man in a suit has shorter arms and the fit of the suit is looser than Patty's pelt. The braincase is dramatically smaller in Patty's case, probably in Homo erectus' absolute brain size. The cranium of the human in the suit is a good deal larger.
The_following pasteup, Image 1, shows the direct comparison in proportionate sizes of the Patterson female (blow up of a still from the film footage, right) and the skulls of Homo erectus above and Homo sapiens below. I have excised the top of the head from the still and put it in the top centre. This section begins at the top of the eye sockets, goes around the top and then cuts off at the back of the neck, level to where the ears would be. You cannot have a human skull in any alternate position when the face is fitted to the mask, human faces do not flex off the skulls. And this interpretation of the size of the face and head are in proportion to the body. Now you can have a suit with a fat padded belly trying to make the head look smaller by illusion, but that would not shrink the actual size of the face or cranium as a fraction of the total height, nor can it possibly change the way they fit together.
This is not an argument that is original to me: Grover Krantz and other supporters of the film have been saying this all along. I defer to Krantz and submit that the creature depicted in the film footage is possibly a surviving Gigantopithecus. And that is based purely on anatomy alone: all other arguments alleging impropriety on Patterson's part or "suspicious circumstances" of any sort, actually have no further bearing on the case nor yet any relevance to the evaluation of the anatomy depicted in the film footage itself.
*UPDATE* Bill Munns (Who created a famous life-sized Gigantopithecus statue frequently illustrated in articles of this type) did a series of analysis-drawings showing what would happen if the Patterson film subject were a man in a suit, how it would bunch up in certain twists and turns, and to establish an absolute size. In general his results tend to fall into line with Krantz. However his illustrations also make an opportunity to illustrate my view that "Patty's" cranium is substandard on a modern human: