Believe it or not, you actually have the ability to take Pictures of ghosts using Kiryu's Xperia during Yakuza 6. These ghosts aren't just of any random person, however, but rather those of the deceased characters from previous Yakuza Games. In order to take a Ghost Photo of these given characters, you must first find one of three photos of said deceased character scattered throughout the game. After finding one of these photos, you will then have to go to a specific location found in the game, usually one that had to do with said deceased character. From there, you will capture the ghost of said character in a Picture by taking a Selfie of Kiryu at just the right angle.
In order to take a ghost photo of Yoshitaka Mine, you will first have to find one of three of his photos found within the game. The easiest one to find is in the NW Theater Square District of Kamurocho, directly in front of the elevator located by the Smile Burger. After finding said photo, head to the rooftop of the Tenkaichi Commerce Building, the same found in directly in front of New Serena, and take a Selfie. If you make sure to include the blue bench in the photo, the ghost of Yoshitaka Mine should appear within the Picture.