The video (which I cannot post) more clearly shows this as a coyote. Somehow moving frames become clearer sometimes. Anyway, I grew up around lots of coyotes, and I feel relatively confident this is a coyote. Objectively speaking though, his tail seems to be almost half the proportional length of the grey fox, compared to its body. The tail seems less bushy as well. Also the total body size of this canid is about double that of the grey fox (or more). I can judge this because the grey fox was previously captured from this same camera in the same position. Also I know this is a coyote because this muzzle is more prominent and missing the dark pattern that grey foxes have.