How can I darken the left side of the sky more than the right?

Steve

Thank you very much for your instructions.

Can I ask one thing - when you say 'duplicate image' does this mean copy and paste in Windows and open both up in CS6?

Next, assuming this is what you mean, I have two files open in CS6 but cannot work out how to show both of them at the same time! I've looked in Preferences and View, tried right clicking the files, but nothing I've come across enables both shots open side by side on the screen.

Whilst looking at the Preferences etc I did start wondering if there is a recommended set-up for CS6 other than the defaults.

Thanks for any advice.

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David