I think I agree with John, the entrance gets that more spooky look thanks to the blackness of the inside, and those two heads certainly don't help, in my opinion it's quite a good photo with great enhancements
Nice photo, I am only a beginner but I don't think you have over done the contrast, it does seem a little over exposed on the out side of the opening, I don't know if you could have done anything else. Cheers John
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