Introduction :

This tutorial covers the creation of an enchanting sketch from a typical, slightly problematic source. It shows how the PhotoGrey and Xpose plugins can lift detail for the creation of the sketch, combined with Thredgeholder Pro edging. The bulk of this tutorial examines each process involved, and at the end there is a visual step-by-step walkthrough.

The Source Material :

The source photograph is of a dark skinned girl. A straight sketch is going to lack tonality, the scene being a fairly flat midrange intensity apart from the collar. An effective transformation is needed to lift the face brightness, focussing on the facial shading. You can copy this image and paste it into your graphics application if you want to work through the tutorial.

Greyscale with PhotoGrey and Xpose :

Using PhotoGrey will filter down to the best greyscale source. The face is rich in red component, so a straight red filter would be best to lighten the face. But the tie is also red and would end up pale too, resulting in an almost white look to the tie in the final sketch. A balance between red filtering on top and less red below should keep the face light and the tie darker. After the image has been filtered with PhotoGrey, Xpose provides a quick and easy way with realtime feedback, to set the brightness and contrast.

Table of Filters and their output after processing by Xpose

Face lifted into light but
red tie is very pale.

Tie darkened but
green top matches skin tones.

Tie and top darker,
face clear. Perfect!


Xpose settings used

The four point gradient keeps the clothing intensities subdued while lifting the red component in the face. The greyscale result can be processed with the Sketcher Plugin using 'NiceSketch.sms' settings for a portrait sketch.

Add Outlines with Thredgeholder Pro :

The Sketcher Plugin produces pleasant shading, but to capture a more realistic sketch key outlines need to be drawn. The Thredgeholder Pro plugin does a great job of drawing these outlines.

Thredgeholder Pro settings used

The LAB's 'l' filtering finds much of the detail in the image but leaves her right shoulder (on the left of the image!) undrawn. The rich green of the clothing means HSL's 's' filter can capture the difference in saturation.

Thredgeholder Pro's output

Final Composition :

To create the final portrait, paste the outline image as a layer over the sketched image with Multiply blending mode. The impact of the edge lines can be adjusted through gamma and layer transparency. In this case, 50% opacity softens the dark lines of the collar, while a gamma of 0.6 to the outline image increases the relative intensity of the finer lines.

The final image!

Step by Step Walkthrough :



Duplicate source




PhotoGrey with 4-point filter


Thredgeholder Pro




Paste as layer
50% Transparency
Apply Gamma Correction 0.6 

Xpose to brighten





Apply the Sketcher Plugin
with NiceSketch.sms settings




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