During a break in filming John Wayne collected his Best Actor Oscar for True Grit (1969) from Barbra Streisand at The 42nd Annual Academy Awards (1970). When he returned, every member of the cast was wearing an eye patch - including his horse.
When Col. McNally, Capt. Pierre Cordona, and Shasta Delaney awake in their camp at the burial site, it is morning, but the lack of shadows would indicate a time closer to midday.