A guy in a blue sweatshirt taking a picture.
A person is holding a Nikon camera.
Just because the person is taking a picture does not necessarily infer that he is holding a Nikon camera.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_take(e1) & n_picture(x4) & (x2 = x3) & n_sweatshirt(x2) & a_blue(s1) & Theme(s1,x2) & n_guy(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_hold(e1) & n_camera(x2) & (x2 = x3) & ne_org_nikon(x3) & n_person(x1))