Reversing ring shooting tips
Adding a reversing ring means that you lose the connection from the lens to your camera, so autofocus doesn’t work. Move the focusing ring of your lens to focus, or physically move your position.
Switch to Continuous shooting mode and fire off a burst of shoots as you move and focus. This way, it’s more likely that some of your shots will be pin-sharp.
Make sure the shutter speed is fast enough to eliminate camera shake. A narrow aperture provides a decent depth of field, but you’ll need to widen it (or bump up the ISO) if the shot is underexposed.
We taped the leaf to a brightly lit window to backlight the vein details. You could also use a reflector (or a small mirror) to bounce light and fill in the shadows.