Robert "Bob" Gilka, who served as director of photography for National Geographic magazine for more than two decades, died of complications from pneumonia at the Sunrise Senior Living assisted living center on June 25. He was 96.

While running the magazine's photography department from 1963 to 1985, Gilka recruited and mentored some of the most prominent nature and wildlife shooters in the business, including Steve McCurry, William Albert Allard, David Doubilet, Bruce Dale, Annie Griffiths, Jodi Cobb and Susan Smith.

According to his colleagues, Gilka's gruff demeanor and high standards often struck fear into the hearts of many young photographers on the magazine's staff. Outside his office, a sign famously commanded visitors to wipe their knees before entering. However, Gilka's willingness to spend freely to let his photographer's follow their artistic visions also instilled strong loyalty among the staff.

One of the most famous images to appear on the cover of National Geographic was one of the last ones under Gilka's tenure. The iconic image "Afghan Girl," by Steve McCurry, almost didn't make it to the cover of the magazine because some editors thought the intense gaze from the young woman would be too disturbing for American viewers. Gilka, however, argued that the image captured the essence of refugee life in the war-torn country and the photo now often referred to as the "Afghan Mona Lisa" was published as the June 1985 cover at his insistence.

Robert Emanuel Gilka was born in 1916 in Milwaukee and studied journalism at Marquette University. During World War II, he served in both the Pacific and European theaters, finally mustering out with the rank of captain. He began his journalism career in Zanesville, Ohio, and was later hired by the Milwaukee Journal, where he eventually took over the picture desk. National Geographic hired him in 1958 as a picture editor.