Many thanks to Jane @jgpittenger for allowing me to have some fun with her tunnel image:
1. Top Left - Jane's image with its nicely abstract feel.
2. It looked like it might invert nicely - hence Top Right
3. It seemed a bit disappointing - wishy-washy - hence Bottom Left
4. I wondered what the changes would have done to the original - hence Bottom Right.
Conclusion - I liked Jane's original version best - just shows you never know until you try!
Cheers Rob