Replacing Skies – (Difficult Subjects e.g. Trees) by Paul Topham

In this workshop, Paul will explain a method of replacing skies around difficult subjects


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Replacing Skies

Open image
Select ‘Channels’
Pick image most contrasty, e.g. Blue or Red (Highest degree of contrast).
Select ‘Image’ (from menu)
Select ‘Calculations’ from dropdown.
Source 1 = Background
Channel = Blue or Red (see above)
Source 2 = Background
Channel = Blue or Red (see above)
Blending = Overlay
Mask = unticked
Result = New Channel
OK.
This creates a new alpha channel – “Alpha 1” under the blue channel.

Menus
Image, Adjustments, Levels (or CTRL + L)
Move arrows -> & <- until foreground is black and sky is white.
OK.
Paint over any holes in foreground with a black brush.

Menus
Image, Adjustments, Invert or (CTRL+i)

(CTRL +) while clicking on the Alpha Channel to create a mask.

Click on RGB Channel.

Click on Layers Tab

Now drag your image using the move tool (V) onto a new background image (sky). Holding down the shift key will make the two images fit together in unison.


To download a printable version of this workshop, click on the link below

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