photorealistic, 8k, realistic, highly detailed, ultra realistic, shallow depth of field, natural light, documentary, realistic photograph, photo shoot, Filmed on 35mm cinematic lens, hyper realistic, photograph, f/1.8, a gigantic turtle with a detailed medieval castle on its back, turtle is underwater and moving slowly, centered composition with the turtle facing forward and looking slightly downward, predominantly blue and gray colors, the turtle's eyes and decorations on the shell glow blue, solemn and mystical atmosphere, realistic textures of the turtle's shell and skin, intricate patterns on the shell and castle, large turtle with a sizable castle on its back, natural light from above, detailed sea and distant structures in the background, no significant foreground elements, turtle's determined expression with glowing eyes, hyper realistic depiction of waves and underwater movement, calm and serene overall tone, vertical orientation, --ar 9:16