Put on your thinking caps, have as many guesses as you want – but most of all, have fun. Your time starts … NOW!
Solved after six hours by Canadian Red Bubbler Linda Bianic, who worked out that the mystery object is a grand piano. This image was shot in the lobby of the Heritage-listed Art Deco-era Hyatt Hotel in Canberra. I used the curved side of the grand piano to reflect the handrail and stairs that lead to the lower level, and the late-afternoon summer light gave me plenty to depict.
I do not crop, enhance or post-edit my images in any way. Shot with a Pentax K100D, using a Sigma 18-125mm lens. F5.6, 1/18, ISO 800, focal length 78mm.