gregg toland collaborated on a number of shots with special-effects cinematographer linwood g. dunn. although these looked like they were using deep focus, they were actually a composite of two different shots. some of these shots were composited with an optical printer, a device which dunn improved upon over the years, which explains why foreground and background are both in focus even though the lenses and film stock used in 1941 could not allow for such depth of field.