Invert, adjust hue and saturation to make grass green and sky blue, curves for more contrast in clouds, USM, resize, USM, save for Web. Forgot that ISO was set to 400.
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Place: 98 out of 438 Avg (all users): 5.6162 Avg (commenters): 7.1000 Avg (participants): 5.4701 Avg (non-participants): 5.8272 Views since voting: 747 Views during voting: 251 Votes: 198 Comments: 12 Favorites: 0
Your positive looks more like a negative to me than your 'negative' does, if you know what I mean. Green is not a negative colour for grass, neither is a blue sky.