this model was trained on landscapes from the Lord of the Rings film: Fellowship of the Ring. Because a lot of the training images were made from matte paintings the outputs have a very painterly feel or quality.
The model is really, really overtrained, or hot. So, I use it at 20% strength for great results (LOTR_background:0.2). Sometimes I'll go up as high as 75% strength (LOTR_background:0.75).
There were people or hobbits in almost every landscape shot. So, a lot of times you might have to use "people, man, woman, walking, children" in the negative prompts for a pure background image.