Although I still have a table top tripod (Neewer 20") which I use for my spotting scope and for my camera when I do astrophotography; I no longer have need for or use a full size tripod.
I now use a long cylindrical bean bag. It is excellent for static birds and wildlife. In the past my main bird set-up was a 7D2 with a EF 400 f/5.6L and the bag was more than adequate for that. I am sure it would also easily accommodate a EF 500L.
Whether I am shooting from my car as a blind or off the side of a tree, this bag provides me with a rock solid platform to shoot from. I got this one at Bass Pro Shop and it was under $20.00.
