Ektachrome is a brand name owned by Kodak for a range of transparency, still and motion picture films previously available in many formats, including 35 mm and sheet sizes to 11 × 14 inch size. Ektachrome has a distinctive look that became familiar to many readers of National Geographic, which used it extensively for color photographs for decades in settings where Kodachrome was too slow.[1] In terms of reciprocity characteristics, Ektachrome is stable at shutter speeds between ten seconds and 1/10,000 of a second.[2]