(in progress) Watermelon Wedge, and Cherries 5x7 canvas panel

I thought I would paint a peice of watermelon today, and a couple of cherries. I have been experimenting with different surfaces, and this time I'm painting on a canvas panel that I had already painted a gray tone on, and let dry. I like it alot! I've also tried other methods, like, painting right onto the gessoed surface, or toning it with thin color and turpentine... so far I think I like the feel of this the best... for right now. So, here's a quick picture of my subject, and the painting I've started.