Product photography of a home sunscreen-application device using a motorized spray ring on a rail, studio lighting, white seamless background, photorealistic, 8k, commercial ad shot. Main unit: a compact wall-mounted base station similar in size and shape to a SodaStream soda maker, matte white and sage-green plastic housing, roughly 32cm tall, with a full-size SodaStream-style CO2 gas cylinder visible through a cutout window (the cylinder should look substantial, about one-third to one-half of the unit's height) and a translucent cream cartridge slotted into the front. From the base station, a slim vertical rail extends, about 60cm long, mounted on the wall — think of a linear motion rail like a 3D printer axis, sleek and minimal, matte white with a thin sage-green track running down its length. On the rail sits a motorized spray ring: an adjustable iris-like ring made of several curved segments (like a camera aperture), roughly 8-10cm in diameter, open in the center so an arm can pass through it. The ring has small visible nozzle openings facing inward on its inner surface. The ring sits on a small sliding carriage that grips the rail, with a visible drive belt or lead screw mechanism. Show the ring positioned mid-rail, encircling a person's bare forearm (the forearm passes straight through the center of the ring), with a very fine, barely visible mist emerging from the inner nozzles, hugging close to the skin — the mist should look minimal and contained, not a big cloud. See more