The magnolia trees were in bloom and the sky was blue with wispy clouds. My original shot with RT's neutral profile. Obviously it could use a dose of RT magic.
After a white balance on the magnolia leaves and a default profile. This version is better but the hidden artist within wanted a bit more ump
The HSV Equalizer tool has been updated and is now less finicky to use. Dragging its blue bar up or down to change the value or lightness of the blue in the sky seemed appropriate. Here is up. It didn't make a massive amount of difference since the sky's value was already high.
And here is down which did. Notice how the blue channel has shifted to the left in the histogram
With the value curve reset I played with the blue saturation curve. Here is up.
And here is down.
With this image it may not be immediately obvious but a judicious use of both the value and saturation curves is a great way to improve skies without going over the top like I'm doing now. The Hue curve rotates the color wheel to create totally aliens skies. This green version is one of many.
After settling on a moderate increase in the sky's value I went on to the CIECAM02 tool. A large contrast boost of 80 made both the sky and the tree far more dramatic.
And to lighten the clouds I upped the brightness to 25.
To bring down the blues I played around with the Colorfullness curve.
And as a final comparison here is where I stated once again.
RT's color correction tools are the best around, period. So load up an image the could use a little sky magic and start dragging curves and sliders. I predict you will like what you discover.