Like other Western U.S. photographers of this period, Moorhouse documented the appearance, costume and lifestyles of native peoples. Many of these characteristics were to disappear under Western cultural pressure. He, like other photographers of the time, depicted a romantic view of their subjects, staging shots to reflect their personal viewpoints and, in doing so, alter details and create inaccurate images. In Moorhouse's case, there are significant differences between two broad categories of his work with native people. His studio portraits of tribal members, which during his lifetime were considered his best work, are stiffly posed and probably inauthentic. Records indicate that Moorhouse supplied his subjects, from an extensive collection of Native American artifacts, with the clothing they wore and the implements they held. In contrast, his images of native life on the Umatilla Reservation accurately reflect native clothing and dwellings of the time. They also document some of the social and cultural transformations that native peoples experienced during this period of cultural conflict. Moorhouse's images have recently been recognized as valuable for eliciting the memories of the past among Umatilla tribal elders, with these stories adding to the archive of the native culture.