In order to transform Jennifer Hudson into Aretha Franklin for Liesl Tommy’s music biopic “Respect,” costume designer Clint Ramos researched both the late star and her culture.

“I had to sort of conjure up what she would have looked like as a child, what her family would have looked like,” Ramos told Variety‘s Jazz Tangcay during a Q&A at the SCAD Savannah Film Festival. “I did a lot of research looking at the church photographs in Black churches and looking at archives, and looking at what those inhabitants of that particular world would look like.”

To imagine those looks, Ramos studied Black culture and the style of the era. “African Americans are independent dressers,” Ramos said. “What would have been the mode of dress for white folks during that time — that was prevalent in all the fashion magazines — would not have been applied to African Americans.”

Ramos also wanted to make sure the designs were flattering for Hudson, who had a different body type.

Ramos said Hudson wanted to be involved in the design process, which was fully collaborative. “She wanted to understand the source of each costume,” Ramos said. “She was so intelligent with trying to understand the choices. She was completely ego-less about the way she was getting dressed.”

Ramos styled and fitted Hudson with 82 looks, of which, only 55 made the film.

He also broke down the craftsmanship behind the famous Amsterdam dress featured on the film’s poster. The dress, which weighed over 40 pounds, was handmade with champagne pearls and Swarovski crystals. “The ‘Amsterdam dress’ is my version of one of her favorite dresses. I believe it’s off the rack because it’s a gold metallic dress, and a vintage dealer contacted me, post-filming, saying, ‘I have another of those dresses.’ I asked her where she got it and she mentioned it was from a department store, Ramos said.

Watch the full video above.