The images were taken with a large view camera, some 4″x5″ and some 8″x10″. Since these cameras are bulky and awkward, I would bring subject-matter into my studio to photograph.
About the platinum printing process:
The turn of the 19th century saw platinum printing at the height of its popularity, but the high cost of this rare precious metal brought about its decline and replacement by the silver printing process. At the present time the platinum printing process is enjoying a revival. Its long tonal scale, soft silver-gray colors, and its superior permanence still make it a favorite among photographers and collectors alike.
Since there is no commercially produced platinum sensitive paper, the artist must make her own by brushing the chemicals onto the paper. Also, since the platinum printing process is a contact printing method (meaning the negative is in direct contact with the paper and thus exposed to ultraviolet light) the negative must be the same size as the desired print. This means the artist must produce a large negative, which requires working with a large format view camera. A 4×5 inch print is made with a 4×5 view camera, and an 8×10 inch print is made with an 8×10 view camera, and so on.