The use of different materials creates a bolder effect. The use of colours and shades adds texture to the image intriguing the viewer. The photographer has created a balance of different materials giving the image unity.
Repetition w/Variation Series of 12 small drawings of an obj. Doesn't req thumbnails. Investigate the obj from diff sides, angles & distances. Make a grid w/12 squares. Consider diff options for establishing a grid. No more than 5% of the piece should be white. Save the white for the brightest highlights. Push your darkest-darks so your obj & lights pop out. Vary line weight. Don't flatten your piece by enclosing the obj in a heavy outline. Consider the balance of the piece as a whole.