It's good fun spotting these wee things. One of the most difficult continuity problems is the guy smoking a cigarette/cigar. Long ash, then short ash then long ash. You have to pity an actor who has to eat heartily because if you have to do the take again he has to eat heartily again, and again. One thing not mentioned is hair styles. It's not so important in a western cos hairy scruff is good, but old photos show meticulously groomed lawmen and Cowboys. I don't mind it in a western but when it's a WW11 movie and we see officers and men sporting curls and locks it's just infuriating. I think I read that in the past the star could refuse period haircuts especially short cuts but now they are contractually bound to submit to authenticity. But me favourite are the clothes especially trousers, sorry pants, worn in the old westerns of the 40,s and 50's BIG wide trousers, sometimes the waist band coming up to the chest just like your grand dad. Now Pappy O'Donnell in Oh Brother Where Art Thou he had some serious trousers in fact when I looked at the movie a week or so I could not look at anything else.