Adding a sketchy effect to a Photoshop image is good for tidying up a rough collage, as well as presenting a loose interpretation of a design idea. It’s one of the techniques we explore in our Photoshop courses for Interior Design.
Open the JPEG version of your mock-up. Go to the layer options and choose Duplicate Layer. This allows for an easy before & after effect by toggling the visibility icon off and on. It also means that you have not changed the original pixels if you need to return to, or sample from, the original image. This is known as non-destructive editing.
Then go to Filter > Blur > Surface Blur > Radius 10 pixels > Threshold 20 > OK. This has the effect of smoothing out the pixels whilst maintaining the edge details. Duplicate the layer again and apply a Blending Mode like Overlay. This will increase the contrast and saturate the colours. To load the luminosity of the image as a selection go to the Channels panel and Control-click on the RGB channel. Note that only the lightest parts of the image are selected. Then Select > Inverse – we now have the darker parts of the image selected.
Now create a new layer and go to Edit > Fill > Use: White > OK. Change the Layer Blending mode to Soft Light, and deselect. You can now toggle the layers’ visibility off and on to see each effect. To create a merged copy of the layers press Control+Alt+Shift+E (Mac: Command+Option+Shift+E).
To apply the sketchy effect first reset your colours to the default black and white, and use the Eyedropper tool to click on a dark colour in your image to set this as your foreground colour. Now go to Filter > Sketch > Photocopy > Detail 3 > Darkness 13. This creates an almost hand-drawn look to the image. And choose the Layer Blending mode of Multiply – this should add a grainy edge to the image. You could now adjust the Hue/Saturation of the image.
To create a grainy, textured look to the whole image first create another new layer and Edit > Fill > 50% Gray. Then Filter > Texture > Grain > Intensity 100% > Contrast 50 > Grain Type: Enlarged. And finally change the Layer blending mode to Overlay.
Many more tips and techniques can be found at the Adobe website. And see many examples of our clients’ work on our Facebook page.
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