Most early photography in the 1880s and so on followed earlier artistic models. Indeed, most of the early photographs were meant to be sold to artists so they could dray from that instead of hiring an expensive model. I answered more in this thread: http://redd.it/3d9upg

The very first images were of landscapes or objects--it was difficult to photograph nudes or people because it took several minutes to take the picture, and people had a tendency of moving--especially if said people were having sex. Regardless, where there is a will, there is a way. When the first commercial photographs went on sale in France, they were available from the offices of opticians, and in the salons of high-end art dealers--not in shady backstreet alleyways (that would come later). The original nude photography was almost painterly. As Dupouy notes:

They mimicked artists and painters by making pastiches of their compositions and the use of accessories, including draping, columns and fabric. In fact, most of the precursors of photography came directly from painting. The interconnection between the two processes seemed obvious: photographers were inspired by painters, and painters made use of photography. With photography, artists no longer had to put up with models who either did not turn up or were late.

Here are some other artistic nudes from that period: NSFW: https://imgur.com/a/nvBdc

If you get your hands on a copy of 1000 Nudes, the Uwe Scheid Collection you can see photographs that seem like they were taken yesterday.