I've always been disappointed by the clean cut and hygienic appearance.The Southern soldiers lack that "rag-tag" look.The uniforms almost look pressed. The short hair, clipped fingernails,clean shaven looks.Beards were few and far between on earlier films.No mud or gunpowder on the uniforms and they all had on a fairly new pair of boots or shoes.Oh, and those pearly whites did they all pack a toothbrush along with the scissors and razor?
I've heard a lot of stories of reenactors going to great lengths in
Gettysburg and
Gods & Generals going to great lengths to avoid the powder puff or whatever they called it from the make up department.
I can't say I worry too much about the "rag-tag" look everyone expects to see from Confederates in film. Its kind of a fiction they were as bad as folks believe. For example you should see them with short hair and without beards, there's plenty of first hand accounts to support that as lice love long hair and beards and thus Confederate dumped the Antebellum fashion of long hair and didn't worry about beards, excepting officers of course. Besides, most of you soldiers were really boys which don't always grow beards.
As for uniforms there would've been plenty or raggedness, and dirty trousers, but they did clean they're clothes, they had to keep them wearable. As for cleanliness and hygiene, there were Confederate officers that mandated this be done, probably most famously Bedford Forrest who was kind of a clean freak from h**l when it came to himself and men under his command.
As for teeth, they did have toothbrushes, plus you can't expect every reenactor to willingly let they're teeth degrade, or a film production spend the extra time and money on the bad look for all they're actors, (it'd cause some actors to have difficulty speaking without practice, and on set time is money), or all the reenactors with close up shots.
Film is entertainment and will never get it all a hundred percent correct, especially considering the numbers of people who are between the heights of 5'4 and 6'1 and weigh 90 pounds nowadays compared to back then. Sometimes you just got to turn your knowledge off to enjoy a film.