Photography is at the heart of visual culture. As with other works of art - unique and high-quality photography can be extremely valuable. When collecting photographs, the rarity should be taken into account. Because photos can be relatively easy to reproduce, it is necessary to determine what makes the photo extraordinary before setting the price. This can be manual colouring, photo manipulation in the darkroom or the fact that the image is part of a limited-edition collection. Photos taken before the year 1950 are usually considered extraordinary, while photographs from the early years of photography (1839-1900) are very rare and often unique. Older photographs usually also have historical significance, which makes them attractive in the eyes of historians and collectors.