Today, I have started rendering Joel's jumper. I started with a pale purple, which was roughly the colour of the palest highlights. Then, I applied a layer of indigo, gradually increasing the pressure as I continued to add to the layers. The amount of pressure applied varied according to the contours of the fabric. This gives the appearance of folds and shadows, thereby adding depth to the drawing. A layer of blackberry was used to tone down the blue and further develop the 3D effect. More blackberry and small amounts of black, in the deepest shadowed areas, will be applied next to gradually build up the intensity of colour.
I used a tortillion, or paper stump, to even out the spread of colour, after applying the first layer of indigo. This helps to smooth out the grainy appearance of the fabric, which would have been fine for a knitted jumper but is too rough a texture for this stretch material. The disadvantage of this technique is that it also brightens the hue of the pigment, but that will be corrected with further applications of blackberry.
At the moment, the jumper seems vast - a lot of pigment will be required to create an impression of realism and it is not the most exciting feature I've ever drawn! However, it is worth giving time to these features as they contribute much to the effectiveness of a portrait. So, back to the drawing board with renewed enthusiasm for dark-coloured jumpers - my favourite subject!!