I agree with Rayraz and tjohn. Basically, there aren't many Bryce renders that are truly photo-realistic. Face it, they are extremely rare, and typically they're of mountains. So, as I see it, you read the rules, and you participate in the challenge. Since you get to vote at the end of it, you can interpret the rules as you wish. Ultimately the collective votes determine what the challenge was really about. If it were up to me though, I would ask the next winner to limit the challenge to just one criteria. Such as Desktop or Realism, but not both. I think it would yield a greater array of images. But, I suppose that's up to the winner.