This is the original image I worked with for this task.
I created this dark, almost horror-like mood using levels, curves, selective colour, hue/saturation and brightness/contrast adjustment layers. I think the dark green tint gives the image a mysterious and disturbing feel, setting the theme for a typical haunted fairground scene.
To create this cheery and fun mood, I used hue/saturation, levels, curves and selective colour adjustment. I think the yellow tone gives the image a happy feel and reflects the joy fairgrounds are traditionally known to give.