The 1873 Winchester barrels and receivers are all unfinished. These metal parts would have been blued making them appear almost black.
Tony Franciosa's knife has the unique look of a WWII Marine K-BAR, although the dark finish has been buffed off, it is not polished but still dull.
Lassiter shoots Rodriguez twice in the torso, but only one bloodstain appears on Rodriguez's white shirt.
Some night time scenes were filmed using a filter to darken scenes. BUT this technique leave the sky blue when in fact the night sky is always black! Further, detail (both close and distant) is evident, when in fact it would, should fade, disappear, into the shadows and darkness of the background.
The Indian girl has pale white legs and it is clear to see that she is not a Native American.
It is clear that a rubber knife is used in the knife fights.
The time setting is 1867, but there are 1873 Winchesters being used.