The over-the-knee position, often abbreviated OTK, is one of the most popular spanking positions. OTK is the classical position for hand-spankings and spankings with a short implement such as a hairbrush or a ping-pong paddle. In photography it was a position very known in daily life and at the same time erotic for those who were attracted by spanking. Either spanking the other one, being spanked or preferring both.
One of the main producers of vintage spanking photography must have been Jacques and Charles Bieder, for their Ostra Studio. They understood perfectly what the anonymous audience needed.
Here is a small collection of OTK photos for you to enjoy from various photographers (as far as I was able to find them) and a few from Jacques and Charles Biederer.