Have you used the photo album in Pokemon Heart Gold/ Soul Silver? I sure hope you have, cause there are some photos which are hard to come by, such as the ones from Gym Leaders. Here's a complete list of when and where they will show up to take a picture with you:
Falkner - Wednesday, all times, Celadon Department Store, register number first.
Bugsy - Friday, all times, National Park. (though I think I've seen him on Wednesday too, can't be sure. It's always the day before the Bug-Catching Contest)
Whitney - Every day, 6pm to 9 pm, Goldenrod Department Store, register number first.
Morty - Friday, all times, path to Tin Tower, register number first.
Chuck - Sunday, all times, Route 47 above waterfall. Will no longer be photographed after Jade Orb is obtained.
Jasmine - Every day, 12pm to 1 pm, Olivine Cafeteria, register number first.
Pryce - Every day, all times, Mahogany Gym. (what a convenient old man)
Clair - Every day, 5pm to 7pm, Dragon's Den, register number first.
Brock - Tuesday, Wednesday, Friday, Sunday, 5pm to 9pm, Diglett's Cave (Pewter City entrance), register number first.
Misty - Every day, 2pm to 4pm, end of Route 25, register number first and must have a Water Pokemon as partner.
Lt. Surge - Saturday, all times, Moomoo Farm, register number and must have traded Pikachu with him (done at Saffron City, in the train station)
Erika - Monday, all times, Celadon City in front of the fountain, register number first.
Janine - Every day, 6pm to 8pm, Victory Road entrance, register number first.
Sabrina - Monday, all times, Olivine Port S.S. Aqua boarding bay, register number first.
Blaine - Thursday, all times, Cinnabar Island, register number first.
Green - Friday, all times, Cinnabar Island, must have beaten Red first.
