The term 'Gradient hair poster shooting image 2015' refers to a promotional or advertising poster featuring a person with gradient hair, which was created in 2015. Gradient hair refers to hair that has different shades of color, blending gradually from one hue to another. This style became popular in fashion and beauty trends during that time. The poster might have been used to promote a hair dye product, a fashion brand, or an event related to hair styling or beauty.