I remember watching this film as a kid, and I didn't really think anything of it. It's fairly crazy what they did; some of those shots seem to be absolutely crazy; must have been some sort of camera trick.
Another interesting thing I discovered is that the large 1800 pound Kodiak, which was also used a lot in this movie, is the same large bear used virtually all of the 80's and 90's movies which had such footage; including White Fang, Legends of the Fall, and The Edge (I highly recommend this one). The large Kodiak was named Bart; he died of cancer in 2000 after a 20+ year acting career.
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