There are some collectors whose passion inspires them to do more than just amass art objects: They become patrons of museums and other institutions, supporters of young artists, educators and arbiters of taste. In the three decades he’s been collecting photography, Martin Weinstein has been a champion of both photographers and institutions that showcase photography. This year, the Minneapolis Institute of Arts celebrated Weinstein’s contribution to photography with an exhibition of 70 prints selected from the more than 300 works he’s donated to the museum. “31 Years: Gifts from Martin Weinstein,” which closes at the end of this month, is a look at Weinstein’s wide-ranging tastes and influence.

Weinstein began collecting photography in the 1970s, after he moved to Minneapolis to pursue his legal career. On the advice of a friend, he introduced himself to Carroll “Ted” Hartwell, then curator of photography at the Minneapolis Institute of Arts, and they became friends. At a time when few commercial galleries were handling photography, Weinstein made many acquisitions for the museum; eventually, he joined its board. After he retired as a partner at a law firm 18 years ago, Weinstein opened Weinstein Gallery and became Alec Soth’s first dealer. The gallery has become a pilgrimage spot for visiting photographers and for classes for local art students. Weinstein, who also donated works to the Walker Art Center and other local institutions, is a man of eclectic tastes, as the “31 Years” show demonstrates. It includes photos by Soth, Margaret Bourke-White, Harry Callahan, Ansel Adams, Robert Polidori and Robert Mapplethorpe. David Little, the MIA’s current Curator of Photography & New Media and author of the catalogue that accompanies the exhibition, says of Weinstein’s contribution to MIA, “In a way, Martin has been almost like an extra curator.”

“31 Years: Gifts from Martin Weinstein” runs through August 31, 2014 at the Minneapolis Institute of Arts. A book by the same name is also available.