Generally, a female porn actress will make less than $1,000 for a standard scene and a few $100 more if it includes anal. Male porn actors make around $200-300 for a scene.
Also, it's not "an hour or so of work". A scene can take up to 6 hours to shoot, and a full day never includes more than two or three scenes. There's also time spent pre- and post-shoot.
Of course, the famous actor will make more, but just as in every other industry, there are very few of them compared to the total.