A photograph (also known as a photo) is an image created by light falling on a photosensitive surface, usually photographic film or an electronic image sensor, such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating such images is called photography. The word photograph was coined in 1839 by Sir John Herschel and is based on the Greek (phos), meaning "light," and (graphe), meaning "drawing, writing," together meaning "drawing with light.
The daguerreotype had shortcomings, notably the fragility of the mirror-like image surface and the particular viewing conditions required to see the image properly. Each was a unique opaque positive that could only be duplicated by copying it with a camera. Inventors set about working out improved processes that would be more practical. By the end of the 1850s the daguerreotype had been replaced by the less expensive and more easily viewed ambrotype and tintype, which made use of the recently introduced collodion process. Glass plate collodion negatives used to make prints on albumen paper soon became the preferred photographic method and held that position for many years, even after the introduction of the more convenient gelatin process in 1871. Refinements of the gelatin process have remained the primary black-and-white photographic process to this day, differing primarily in the sensitivity of the emulsion and the support material used, which was originally glass, then a variety of flexible plastic films, along with various types of paper for the final prints.
Panoramic format images can be taken with cameras like the Hasselblad Xpan on standard film. Since the 1990s, panoramic photos have been available on the Advanced Photo System (APS) film. APS was developed by several of the major film manufacturers to provide a film with different formats and computerized options available, though APS panoramas were created using a mask in panorama-capable cameras, far less desirable than a true panoramic camera, which achieves its effect through a wider film format. APS has become less popular and has been discontinued.
Ideal photograph storage involves placing each photo in an individual folder constructed from buffered, or acid-free paper. Buffered paper folders are especially recommended in cases when a photograph was previously mounted onto poor quality material or using an adhesive that will lead to even more acid creation. Store photographs measuring 8x10 inches or smaller vertically along the longer edge of the photo in the buffered paper folder, within a larger archival box, and label each folder with relevant information to identify it. The rigid nature of the folder protects the photo from slumping or creasing, as long as the box is not packed too tightly or under filled. Folder larger photos or brittle photos stacked flat within archival boxes with other materials of comparable size.
Because daguerreotypes were rendered on a mirrored surface, many spiritualists also became practitioners of the new art form. Spiritualists would claim that the human image on the mirrored surface was akin to looking into one's soul. The spiritualists also believed that it would open their souls and let demons in. Among Muslims, it is makruh (offensive) to perform salah (worship) in a place decorated with photographs. Photography and darkroom anomalies and artifacts sometimes lead viewers to believe that spirits or demons have been captured in photos.