Television has a split image: one by day and another by night.

In the daytime, blacks and other people of color are a prominent presence, hosting popular talk shows and playing juicy roles in soap operas. But at night, minorities are largely sidelined, with white performers holding most of the marquee roles.

The industry's Jekyll-and-Hyde approach to diversity is underscored by the controversy engulfing NBC's "Saturday Night Live." The sketch comedy series came under fire from within its own ranks and from outside observers who decried the show's long-standing lack of ethnic diversity.

In its 38 years, the show has had only four African American women as regular cast members. Just 10 black men, including current performers Kenan Thompson and Jay Pharoah, have made the roster.

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No black women have been regulars since Maya Rudolph left in 2007.

"SNL" producers attempted to make light of the situation by having last week's guest host, black actress Kerry Washington, play First Lady Michelle Obama and Oprah Winfrey (and almost Beyonce) in quick succession, underscoring the fact that there weren't any other black women to play the roles.

Network executives say they are committed to increasing diversity — especially in prime time, when most people are watching. But daytime programmers have aggressively been recruiting prominent black personalities, giving Queen Latifah, Cedric the Entertainer, Steve Harvey, Michael Strahan and others plum shows that have drawn huge audiences.

When the sun goes down, much of that cultural flavor drains. Only a handful of returning network series — including ABC's "Scandal," starring Washington; Fox's "The Mindy Project," with Indian American actress Mindy Kaling; and CBS' "Elementary," with Asian American actress Lucy Liu — feature minorities in lead roles.

The contrasting pictures reflect different economic approaches and expectations: The audiences and budgets for morning and afternoon shows are considerably smaller than for programs in prime time, where the risks are greater and more expensive. Television executives also develop shows with an eye toward international markets, and they worry that some foreign buyers might be less likely to buy a show with an ethnic lead.

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"There's a lot more at stake in prime time, with productions that involved large casts, a slew of writers and technicians," said Darnell Hunt, head of the Ralph J. Bunche Center for African American Studies at UCLA, which is conducting an analysis of the diversity of casts on cable and network series.

Looking for the broadest possible appeal, Hunt said, network executives almost always favor white leads for prime-time shows.

When characters of color are cast in those nighttime shows, he added, they "are part of an ensemble — the shows are not about them. In daytime, the people of color can be the star — the host of a game show or the head of a talk show."

Daytime programmers said President Obama's election prompted them to consider retooling their lineups to add more racially diverse personalities. In 2010, Steve Harvey became the first African American host of the game show "Family Feud." Ratings began to climb and then skyrocketed 40% last year to an average of 7 million viewers — the 37-year-old program's highest ratings since 1990.

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Cedric the Entertainer, who became host of Walt Disney Co.'s syndicated "Who Wants to be a Millionaire" show in September, thinks black actors and personalities can draw big audiences in prime time if only they are given a chance.

The problem, he said, is that there are too few minorities in positions of power in the industry.

"It's that combination of economics and not having that voice in the boardroom who understands our story, our humor and our point of view," Cedric said. "Jerry Seinfeld and Ray Romano did not have shows that started out as juggernauts, but there was somebody in those boardrooms who understood them and had faith."

That said, there are more blacks behind the scenes now than in the past, including Shonda Rhimes, the executive producer behind the ABC shows "Scandal" and "Grey's Anatomy, and Pearlena Igbokwe, a top programming executive at NBC. And of course, one of the biggest TV stars of any race is Winfrey, who came to fame on daytime.