The most basic would be the combination of an image of the sky and an image of the earth. The reason was to have correct exposure for both the sky and the ground when shooting a landscape. For example, if the photographer measured the correct exposure for the terrain and took the photo, the sky would be puffy and overexposed. This results in little to no detail in the sky. To solve this problem, combined printing was created. It required at least two different downsides, so it was “complicated, time-consuming, and expensive” (Hirsch 92). One negative would have correct exposure and detail in the sky and the other in the ground. Photographs caught on and amassed properly exposed negatives of the sky to use for future landscapes. However, those are only with two images. They can get more complicated. For example, artist Oscar Rijlander used 32 negatives to make a print. This refers to modern use with Photoshop. Photoshop essentially allows the artist to combine prints. There are several ways to combine images in Photoshop. You could copy and paste something into an image. Or stack them on top of each other and erase some parts using masks. Whichever Photoshop process you choose to use, it's very similar to the combination