If you enjoy historical reenacting, in my case the american civil war, you can learn a lot about what types of clothing, hairstyles, furnishings, and even mannerisms are correct for the time you enjoy recreating from examining photos of people, places and things of that time.  Many times fellow reenactors/living historians will disagree about the correctness of a certain aspect of their portrayal.  I have found that by studying historical photos, volumes are available on the internet and are for sale as well by Ebay sellers, the details learned from photos of actual people living during their time is a very inexpensive and yet priceless way to improve your impression.  When you want to know if it was truely right or not, remember, A picture tells a thousand words...