Macro with a ring flash

This is a Virginian tiger moth caterepillar I photographed in my backyard. I found it crawling on some grass. I used a ring flash for the illumination for two reasons: 1) I wanted to simulate diffused daylight to minimize or eliminate contrast, and 2) I wanted enough light output to compensate for the diminished light with the use of f/32. The small aperture gave me as much depth of field as possible notwithstanding focus stacking which was impossible because the caterpillar was slowly moving. The flash used very close to the subject -- about 5 inches away -- would result in a very dark or black background. Therefore, I set up a 13x19 inch print of out of focus foliage behind the insect. With that in place, I could close the lens down as much as I wanted and the background would still appear completely out of focus and undefined. I handheld the camera and flash, and this worked because the magnified movement associated with the 50mm macro lens didn't affect the sharpness of the picture. The brief flash duration took the place of a fast shutter speed. My shutter speed was 1/125 which I used to sync with the flash, and the ISO was 100.