In this shot of the UK Royal Family on the balcony of Buckingham Palace, Prince Charles (as he was then, he's now King Charles) face is a bit too dark, as is Camilla (now Queen Camilla). The Queen's face is not as dark, but could benefit by slightly lightening.

These are tasks that are suited to the Adjustment Brush. If you need to lighten or darken a larger area, you would often be better making a selection.

The pink overlay shows very clearly where you have painted, but it makes it harder to see the result of the adjustment.

You can toggle this on and off, even later when you want to see where you've brushed, or edit the adjustment.

When you select the Adjustment Brush and make an adjustment, the Brightness & Contrast adjustment is automatically selected and at their default starting values of 50.

We want to lighten their faces, not increase contrast. Increasing contrast will darken the shadows.

You can adjust the settings, if you wish to use Brightness & Contrast. In this case, I would set the contrast back to zero and then adjust brightness accordingly.

Here is the original.

This is the result of using the Brightness & Contrast adjustment at its default settings of 50.

Highlight detail on Charles face is being lost.

This is the result of using Levels to brighten the faces, without increasing the contrast.

Yes, they could probably benefit by a slight increase in contrast though not as much as the previous step.

Any increase in contrast should be made to the whole image, not just a few selected faces, which will then look different to the others in a noticeable way.

Select Levels from the adjustment dropdown menu.

It will be applied with default settings, as all these adjustments are.

The Black slider (highlighted in red) has been moved to the right, making the dark areas darker.

The White slider (highlighted in green) has been moved to the left, making the light areas lighter.

These default settings increase the contrast, much like Brightness and Contrast settings.

That's not what we want, so we'll reset them in the next step.

Click on the reset button, highlighted in red. This is at the bottom of the Properties panel, which will show the Histogram while you edit Levels. If the Properties panel is not visible, you can open it from the Window menu: Window > Properties.

Settings are set back to zero. No change, until you make a change.

Levels are reset to zero, with no adjustment being made.

When you move the black and white sliders towards each other you are increasing contrast. That's not really what we want here, especially just on selected faces. We just want to lighten the faces slightly.

I have dragged the middle slider to the left to lighten. The black and white sliders have not moved.

As soon as you make your first brush stroke, an Adjustment Layer is added to the Layers panel, complete with a Layer Mask, showing where you've brushed.

The great thing about this is that Adjustment Layers are non-destructive and permanently editable, with no loss of quality. To preserve the Adjustment Layer (and any other multiple layers) you will need to save the image either in the .psd or .tif formats. These formats support layers, whereas a jpeg does not.

If you opened a raw file, you will also need to save in the .psd or .tif formats, as the raw file can't be edited.

When a Layer Mask is added to a layer, or an Adjustment Layer is added from the button at the bottom of the Layers panel, it is white. On Layer Masks, white reveals, showing the contents of the layer it is on. When you use the Adjustment Brush and an Adjustment Layer is added, the Layer Mask is black, which hides, with the areas you brushed shown in white. So it only shows your adjustment.

If you continue brushing in different places in your image, they will all be applied to the same Layer Mask and receive the same adjustment.

If you want to apply a different adjustment, you need to select the layer it applies to, then create a new adjustment.

But note that even after selecting a different Adjustment, such as Levels, the next adjustment you make will automatically revert back to the default Brightness and Contrast Adjustment.

So each time, you need to remember to select the adjustment that you want and then also reset the settings back to zero before making adjustments.

You can edit an existing adjustment by double clicking the layer thumbnail (highlighted in red).

As the screenshot shows, the original has not been changed (the layer is still locked).

When you double click the thumbnail of an adjustment layer you will open up the settings, just as you left them, however long ago that was, provided you saved the image in the .psd or .tif formats, which support layers.

The above example looked at manually painting your adjustment with the Adjustment Brush. That is perfect when you need to adjust, generally, a small area. If you want to apply an adjustment to an object, you will probably need to be more accurate than painting with the brush.

One option you have when using the brush is to select the Select Object option. You can either do this from the Options Bar, or from the Contextual Taskbar.

We'll do that here to change the colour of the postbox. In the UK postboxes are always red, (except some are painted gold, in their home town, to commemorate Great Britain gold medeal winners at the 2012 Olympic Games, hosted in London).

Select Hue/Saturation from the Adjustment dropdown list, either in the Options Bar in in the Contextual Taskbar, (highlighted in red). If the Contextual Taskbar is not visible, you can open it from the Window menu, (very close to the bottom of the menu).

Select Apply to object, (highlighted in green)

Move the cursor over the object and watch for it to be selected, as indicated by a pink outline. If this is successfully selecting your object, just click once.

The selection is automatically applied to a Layer Mask on your Adjustment Brush layer.

The Layer Maskk is highlighted in green.

The Layer thumbnail is highlighted in red. Later, if you want to edit this adjustment, double click the layer thumbnail. You will then see the settings exactly as you left them (provided you save in a format that supports layers, like .psd or .tif.

When you use the Adjustment Brush, it adds an Adjustment Layer. Whenever you use an Adjustment Layer, the details can be seen in the Properties panel, as shown.

If the Properties panel is not visible, you can open it from the Window menu: Window > Properties.

The Properties panel shows the results of the tool you are using, but this includes all tools, depending on which you are using at the time.

The screenshot shows the Hue/Saturation before changes are made. The Hue slider is set at 0.

The Hue slider has been moved to the right, as shown.

The result is shown in the next step.

This is the result of the previous adjustment, described above.

If you save this in a format that supports layers, such as .psd or .tif, you can always edit this adjustment and in this case, change colors, just by moving the slider.

As mentioned above, you need to double-click the Adjustment Layer thumbnail.