Even with a dizzying ask of $12.8 million, you know you’re headed for off-the-charts territory when a 4,200-square-foot, three+ bedroom apartment starts with a sunken foyer that opens into an 800-square-foot sunken living room. And if you’re thinking that’s bigger than lots of people’s entire apartment, consider the fact that there are many rooms like it in this full-floor home in the Photo Arts Building at 5 East 16th Street. And you haven’t even seen the atrium wall yet.

More enthusiastic modern design, this way