If you found an old picture and wish to take a shot of the after-picture, it is best to first make a printout of the before-picture or copy it to your smartphone. Once on site, you then take a sample shot and compare it with the old photo, and then correct your position if necessary. In order for the images to overlap well after subsequent alignment, it is important that the perspectives from which the two photos were taken are as close as possible to one another. The more the perspectives differ, the more distorted the images will be later. The transformation capacity using markers is not unlimited and depends on this first step.