"Merlin" is a UV (ultraviolet) blacklight fluorescent and glow-in-the-dark phosphorescent
t-shirt / hoodie print, made from the original psychedelic spiritual visionary fantasy fine art backdrop painting by Symeon Nostrakis, and depicting the Mystery of Magic and Sorcery:
Merlin the Wizard wearing a Triscele Amulet, holding a Black Obsedian Magic Sphere
and a Magic Wand shooting Seven spiralling Rays of Rainbow colours which correspond to
the 7 Alchemichal Metals, dressed in Lapis Lazuli Blue Robes adorned with Golden Yellow Stars and Half Moons, standing on a Field of Amanita Muscaria (Fly Agaric) Mushrooms,
under the Starry Night and the Space filled with Stars.
If you don't have a UV black-light, the t-shirt/hoodie will still glow in the dark and of course be visible in normal light.
For better glow-in-the-dark results place t-shirt/hoodie near a bright light source and allow at least 30 minutes for charging.
The brighter the light and the more time the t-shirt/hoodie is exposed to it, the more energy it will absorb and the more it will glow.
Additionally, the darker the room when you switch off the lights, the more pronounced the night glow effect will appear.
A black light source will charge the t-shirt/hoodie better and will make it glow more than a normal light source would.
Alternatively, you can use fluorescent lighting for charging (FT tubes or small CFL economy lamps).
Old incandescent lamps cannot provide sufficient charging as they do not emit UV light.