Is this a good donor area? (Photo)

You cannot assess the donor area with a photo.  It just looks like you have lots of hair like most men with hair loss.  If you are an average male with hair loss, your donor area should be average.

Your photo must have been before the FUE procedure, but from the photo it does look like you have good donor hair. When we evaluate donor hair, we look at both the quantity of donor hair (density) and the quality of donor hair (caliber). Your hair looks good from both aspects.

Based on the photo, your donor area looks very dense. I would say the shaft diameter of your hair and the density are both above average,
Dr. Robert Jones

To determine the value of the donor area the doctor needs a hand microscope to measure the follicular unit density present. That will tell you much about your total donor supply

I would have to agree, the donor area looks good. You should be able to safely get at least 4000-5000 grafts from this area over the course of your life without any overharvesting.