I'm trying different products than I usually use. The underpainting is as far as I have progressed, and is done with a mix of NeoColor II watersoluble crayons, and Inktense watersoluble ink pencils. I find that the Inktense are easily sharpened and you can get into some smaller spaces.
The photo resource I am using is from Stock Xchng taken by Mehmet Goren. I have been using it for a class exercise.
Step 3. The shadows of the stem of the tomato have been underpainted with Bark and Fuschia Inktense. Highlights have been added with White Neocolors.
Step 2. The shadows of the tomato have been underpainted with Leaf Green Inktense, and Green Neocolor.
Step 1. The background has been underpainted with Black, Blue and a bit of Purple Neocolors.