Photoshop CS: using a shape to adjust a single part of an image

I have a pic with a palm tree being lit by a string of christmas lights. I have adjusted the image to may taste but the area where the lights are have too much light.

I saw a tutorial about 4 months ago where the instructor used a shape to modify a clock on a wall. As my memory serves me in a spotted fashion. He simple drug a circle around the clock and adjusted the luma and choma in the clock.

can anyone give me a walkthru of how this is done?

Photoshop CS / Mac 10.5.6 / Intell 3.0 Quadcore

You need to read up on selections and masks. There are many excellent video tutorials out there, which you can find through Google of course.

Basically you want to create a selection of the area you want to modify and turn it into a mask.

Photoshop CS / Mac 10.5.6

That combination is known to cause a multitude of issues, and that's why it's not supported by Adobe. :/

I almost forgot i will need to feather the edge for blending purposes.

Feather the selection…

Yes feather. What i have done so far because i cant seem to use the shape is.........

I duplicated the background layer and adjusted the duplicate to be very dark. Then used the eraser tool with 25% hardness to erase all but what needed to be darkened.

Its not the best blend between the dup. layer and the actual background but its not horrible. I wish i could show you.

Use layer masks, not layer duplicates.