He is the co-founder of the magazine Zenith, one of the leading publications about the Middle East and the Arab world in Germany, and is a founding member of the German non-for-profit organization Candid Foundation.

[1] Mettelsiefen was born in Munich to a German father and an Ecuadorian mother and began taking photographs after graduating from high school.

[2] At the beginning of the Arab Spring, Mettelsiefen traveled to the besieged areas in Egypt and Libya for the news magazine Der Spiegel.

[3] One of Mettelsiefen's best-known films is the short documentary Watani: My Homeland, which tells the story of children in war-torn Syria.

[7] His latest feature documentary, In Her Hands premiered to great acclaim on the opening weekend of the Toronto Film Festival 2022 and was sold to Netflix.