"A common mistake" in photographing lesbian couples happens when "one wears the pants and one wears a gown," according to Hamm. "We basically pop them into male and female roles. It's very complex, but there are aspects of gender expression that transcend sexual orientation. The bottom line is to understand how the couple is comfortable being themselves."
Guessing the power dynamics and staging a pose, such as asking the bride in pants to classically "dip" her partner in a dress, or suggesting one groom embrace the other without an understanding of how they relate to each other, can be "at best, awkward, at worst, offensive," she said.
At Hamm's wedding on Maryland's Eastern Shore during Hurricane Dennis, both brides wore champagne and ivory dresses with sandals, their toenails painted blue.
She and her partner had little guidance because few same-sex couples had even contemplated the institution of marriage 14 years ago.
"Legal recognition was not part of the conversation -- it was a smaller, more private ceremony situation," said Hamm. "For most folks, it had not occurred to them to do this then. But those who did, wrestled with what does it look like and why does it matter?"
As for the cultural shift that has happened since the couple first met, Kathryn Hamm said, "It's astonishing how much things have changed. More products are in neutral language. Instead of a bride and groom, the symbols are diverse -- two glasses or two doves. There is a much broader range of tasteful stationery lines. Couples can find more cake tops with themselves in it -- two grooms and two brides and mixed-race couples."
"What is important is to see ourselves reflected and embraced," she said.
Gretchen Hamm, whose loving attitude jump-started Hamm's career, said she never hesitated when her daughter wanted to make a lifelong commitment to another woman.
"We are a very close-knit family," she said. "We love Kathryn no matter what, but our script looked different. All of a sudden we had two daughters-in-law and son and a daughter. Nonetheless, we loved her and embraced her."
Gretchen Hamm hosted a wedding reception for the couple in Dallas among friends for whom the concept of gay marriage was "totally new."
"They were so open-minded and I realized that it is a lack of education and not about prejudice for the most part," she said.
Kathryn's father was more hesitant, but when his daughter wanted to formalize her commitment in a ceremony, he quickly changed.
"It was the language of a wedding that he understood. It meant that we had crossed a threshold," said Kathryn Hamm. He even sang in the wedding.
Both grandmothers also attended, even though they did not fully agree with the idea of same-sex marriage.
But, said Hamm, "It's undeniable when you are in a room with two people who promise themselves to love and commit -- all the things my family is about. You can't help but support them."