I like the concept and it's well executed; however I think the frame could have been composed better to eliminate the structure on the right side and the blownout spot in the hourglass. There's also a large blurry blob in the sky on the left side - probably a bird flying through.
Nice subject, however it is underexposed, noisy and not completely focused. You need to have defined edges of the main subject. Please zoom to between 100 and 200% to inspect for details, and to make sure your photos meet the criteria as outlined in the contributor guide and here.
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Good lighting is important. While you're learning, try to shoot photos during peek daylight hours when the sun is directly overhead or behind your shoulder. Low light shots are very challenging even for experts.