Note (after you stop laughing) how dark Buster's hands are compared to his face.
The secret lies in the type of film stock. Not all black and white film was created equal! Before 1922, almost all motion pictures were shot on orthochromatic, or blue-sensitive, film:
The film stock was sensitive to the blue-violet end of the visible spectrum but insensitive to the yellow-red end which meant that it registered reds and yellows as black and light blues as white. Some orthochromatic film may also have been used; it was very sensitive to violet light, considerably sensitive to blue and ultra-violet, much less sensitive to green and yellow light and insensitive to red.
This is one of the reasons actors with blue eyes were not commonly utilized; their eyes simply wouldn't register. I don't have the book in front of me, but I do remember Colleen Moore mentioning in Silent Star that she feared her movie career might be ruined for this very reason.
Because even the slightest tinge of red would register as uneven and dark, "photoplayers" laid their pink and white greasepaint on with an extra-heavy hand. It worked, but also gave them a masked, ghostly look. This also forced them to heavily blacken (or sometimes redden) around their eyes in order for them to be visible. Actresses' lip rogue would also register as black, completing the odd transformation.
(Granted, Musidora is supposed to look ghoulish here, but you get the idea.)
By 1926, the price of panchromatic film stock was finally affordable to everyone, and the look of actors became softer and more natural. Advancements in cosmetics by Max Factor and the Westmores meant stars no longer had to rely on stage greasepaint. These new products however were still harsh:
The lovely Dolores Costello was blessed with a very fair, perfect, and delicate complexion, and she developed severe reactions to the harsh makeup then used in her movies. The skin on her cheeks began to deteriorate, and artists found her condition impossible to hide. Her beauty ravaged, poor Dolores was forced into retirement after her final film...
The Goddess of the Silent Screen herself (image courtesy dolores-costello.tumblr.com )
I love learning about the history of cosmetics and their application, particularly how it developed in leaps and bounds thanks to the film industry. They truly were sister industries.
Tell me, readers: would you like to hear more?