I felt so dumb when I realized that I didn't actually need any sort of special adaptor.
In a pinch, a 1/4 thread bolt could be used and you would just have to cut the head off. It would be wise to cut a groove at the same time so you could at least use a flathead screwdriver to remove it.
This bolt allowed me to mount the Velbon QR plate upside down to the other side of the Giottos tripod.
Add photograph to your favorites
Add photographer to your favorites