good focus and lighting. minor things that detract are the less-than-black background elements (brown fabric or something) below the clock and the minor dings and scrapes in the clock. these things add too many distracting elements and take away from the shapes and subtletes of the clock. 5.
I like your composition here. The clock in the lower left seems to introduce the void behind it and combined with the low key and potentially ominous title, suggests that the void is filled with mysterious things. The shadow on the face of the clock distracts me just a tad, perhaps because of the harsh shadow? Nice work.
Great shot and fits the challenge well. I love the shadowing on the hands of the clock. Great lighting. Good luck. I sure hope your not getting hammered for this.