Hands on: Add digital effects to images

Paint Shop Pro effects
Paint Shop Pro’s users are almost as well served in the lighting department as Photoshop’s. To access Paint Shop Pro Photo XI’s Lights dialogue box, select Effects>Illumination Effects>Lights. This dialogue box is similar to Photoshop’s and, although the range of effects and controls isn’t quite as versatile, at least the Paint Shop Pro dialogue box is resizable and you can preview the effect live in the picture window.

Paint Shop Pro has five lights and, rather than adding or removing lights from the image, you simply switch them on or off. Like Photoshop’s, you can reposition or angle them, and adjust the spread of the beam by dragging and dropping and adjusting handles. Paint Shop Pro doesn’t have different light types, but offers versatile adjustment options, which makes them all but unnecessary.

Cone Size can be adjusted from 1º to 90º so you can produce highly directional spots, or diffuse lighting, along with everything in between. Smoothness controls the rate at which the light fades. At higher settings, it simulates real-world light, which fades in proportion to the square of the distance. At lower settings you can use the Smoothness control to simulate a shaft of directional light coming through a door or window.

Paint Shop Pro has fewer lighting presets than Photoshop but, given that you don’t have to add lights to get started, they’re even less useful. What is useful is that, having created your own lighting setups from scratch, you can save them for later use on other images.

DIY lighting
You don’t need a lighting filter to create lighting effects; you can achieve a similar effect quite easily by making tonal adjustments and limiting them to part of the image using selections. The technique I’m about to describe uses a simple selection saved to an alpha channel. If your application doesn’t support alpha channels, just use the selection directly on the image layer.

First you need to duplicate the background layer: in Photoshop you do this by dragging it onto the New Layer button in the Layers palette. Press Ctrl & L to open the Levels dialogue box and darken the layer by dragging the white Output Levels slider on the right of the ramp towards the middle. Keep dragging it until the number in the box above it is about 160. What this does is clip the image highlights so that all of the pixels with a value above 160 are lowered.

Next, make your selection to define the light path using your preferred selection tool. For this example I used the Polygonal Lasso. You need to ensure that the selection extends to the image boundary, or the light will come to a halt abruptly.

Now choose Save Selection from the Select menu and call the new alpha channel ‘light’. Click the channels tab in the Layers palette and select the light alpha channel, then apply the Gaussian blur filter to soften the edges. Make sure to deselect (Ctrl & D) before you do this or the blur won’t work properly.

Go back to the Layers tab, select the background layer copy, then choose Select>Load Selection to load the soft-edged selection back in. Click the New Adjustment Layer button on the Layers palette, select Levels from the popup menu, and drag the right-hand output slider to the left to lighten the masked layer.

That’s basically it, although there’s plenty more you can – and probably should – do to add a bit more realism to the effect. For one thing, the light is consistent across the image, whereas in reality it would be brighter closer to the source. You can fix this by adding a gradient fill to the adjustment layer mask. Edit the mask using brush tools to add and remove light to enhance the effect and make it more realistic. You can keep light out of the shadows this way.

It helps a lot if you choose your lighting effect to fit with the existing ambient lighting and shadows in the shot, as I’ve done in this example. Plus you can make the light run behind foreground objects.

All of this can add up to quite a lot of work. If you haven’t got the patience and adding light is something you find yourself having to do frequently, have a look at dft Light. This Photoshop plug-in – which will work with Paint Shop Pro and other image editors that support Photoshop plug-ins – does everything that the lighting effects filters can do and more.

One thing it’s particularly good at is casting shadows. In the bad old days this was done by placing a gel with the shadow image over the light source. Light 3.0 uses masks – there are 567 from which to choose – to simulate light shining through anything from trees and iron railings to elaborate window frames.

If you can’t find the template you need (and to be honest there are a fair few – for example, eagle with crest, Paul Revere and the Liberty Bell – you’ll likely never use), you can make your own.

But the killer feature is displacement maps. Unlike the channel bump maps used by Photoshop’s lighting effects, rather than adding texture these deform the light path so it appears to follow surface contours. dft Light 3.0 costs $50 (£25) and a 30-day trial download is available from the dft website.