[STEP BY STEP]
REMOVE UNWANTED CLUTTER
USE THE CLONE AND HEALING TOOLS IN COMBINATION TO CLEAR UP A MESSY FRAME.
01 MAKE A NEW LAYER
With something as fleeting as the Northern lights, there’s very little time to compose the perfect frame, but you can use the Clone tool to remove the clutter. Press S to activate the tool, then go to the Layers panel (‘Window > Layers’) and click the ‘Create New Layer’ icon at the bottom.
02 CLONE OUT THE CLUTTER
Set Sample to ‘All Layers’ at the top. Begin removing the clutter from the scene by Alt-clicking to sample nearby tidy pixels, then using the sample to clear the mess. The tool works well in combination with the Spot Healing tool (J), which can also be set to Sample All Layers.
The Clone tool simply lets you copy pixels from one area to another. Hold Alt to target an area, then begin painting to clone the pixels. While you’re using the tool, press the Alt key regularly to repeatedly sample a source. The source moves with your brush strokes unless you untick ‘Aligned’ in the options bar.
CLONE SOURCE PANEL
Go to ‘Window > Clone Source’ (or click the Clone Source icon in the tool options) for controls that let you alter the size — here, we’ve cloned a 40% version of the house — and the angle of the source as you clone, so you can tilt a cloned object or resize it. It’s useful to keep the overlay view turned on so you can get an idea of how the cloned area will look.
CLONE AND BLEND
The brush blend dropdown in the Clone tool options let you add in a Blend mode as you clone. For example, you could choose to clone using the Color Blend mode like this to recolour an object. The modes will only blend with pixels on the selected layer, so an empty layer won’t work here: you’ll need a duplicate of the background layer.
You don’t often need to use the Clone tool at full opacity. More often than not, it’s best set between 20–50% tool opacity. There are many uses for this, from tidying up rough patches caused by the healing tools, to softening wrinkles and eye bags in portraits.
THE SAMPLE SETTING
The Sample dropdown in the tool settings at the top lets you control whether the tool samples its source from the selected layer or elsewhere. The All Layers option is useful for cloning non-destructively on an empty layer at the top of your layer stack.
With the Clone tool selected (or any other tool with an Opacity setting), you can press 1 for 10% Opacity, 2 for 20% and so on. Press ] and [ to resize the brush tip, ‘Shift-]’ or ‘Shift-[‘ to alter hardness, and Shift-click between points to clone in a straight line.
VANISHING POINT CLONING
Use this filter to clone along the perspective of an object.
The ‘Vanishing Point Filter’ found under the Filter menu  lets you clone in perspective. Here you can use it to clone over the awnings  and tidy the face of the building, using the nearer building details as a source . This wouldn’t be possible with the conventional Clone tool due to the perspective of the building, but with the Vanishing Point Filter, it’s quite a simple job. Click on four corners to plot out a plane over the rectangular face of the building using the Create Plane tool , then grab the Clone tool . Use the settings at the top of the dialog  to resize the brush tip, then Alt-click to define a nearby source before cloning over the awnings to remove them.