If you were to ask Roger Patterson who filmed his now infamous Bigfoot film on October 20, 1967, he will naturally reply in the affirmative as he has been doing exactly that since the day the film was shot until his death due to cancer in 1972. His proponents, like the anthropologist Grover Krantz, believe it is real. Krantz even made a detailed examination of the film and presented it to other experts for them to take a look and put in their two-cents worth. He concluded that what he saw on the Patterson film was a manifestation of a truly genuine yet unknown creature on the basis of its gait, the extreme width of its shoulders, the way its knee was bent more than 90%, and its natural-looking muscular structure. He also cited his impression based on his interview with the man that Patterson lacked the ability and the technical knowhow to make such a detailed and realistic costume or representation of bigfoot. Detractors of Patterson, however, like anthropologists David J. Daegling and Daniel O. Schmitt, who have also examined the film have pointed out that based on the film alone, it is not remotely possible to conclude with certainty on the identity of the subject.