The Civil War photographer Mathew Brady had to travel with a mobile darkroom in a wagon. The wet plate process with which he worked produced amazing negatives and an irreplaceable record of that bloody conflict. But the process was so slow, so fragile, and the cameras so large, that actual combat pictures were impossible. It is fascinating to read about the lengths that early wildlife, documentary, and expedition photographers Martin and Osa Johnson went to in order to bring back never-before-seen images and films from the South Seas, Africa, Borneo, and elsewhere. That Frank Hurley’s sublime images of Ernest Shackleton’s ill-fated 1915 Antarctic expedition were even made, let alone survived, is nearly unbelievable. John Noel ‘s footage and photographs from the 1924 Everest attempt where Mallory and Irving lost their lives took a nearly inhuman effort to shoot and then develop in a high-altitude field darkroom. Taking photos with early cameras in what are still the most unforgiving, deadly, and difficult mountains, jungles, and ice fields of the world is scarcely believable. But the images exist to prove it was done and the more you learn about these feats of bravery, endurance, technical skill, and artistic genius the more you realize that as photographers and explorers we truly rest on the shoulders of giants.