I've never tried moving a camelia that large...I did move two that were about 4'x 3' with no real trouble. I dug out to the drip line and got as much of the root as possible. It took some real digging to do it, so I could only imagine what it would take to move yours. If your camelia blooms in late winter/early spring I would move it in the fall or when the weather is cool. If it blooms in the fall, I'd wait to move it next spring if possible. If not, I'd once again wait until it cools off... you may lose some or all of this years blooms due to the stress of moving it.
Make sure you water it well and keep watering it until it is established in its new home. Good luck!

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Well, for better or worse, it's done. THere was a much smaller rootball than I expected, still HEAVY, but looked disproportionately tiny. I hope it will take hold in its new home!

The side of the camellia now facing the yard is the shady side, so I hope we'll see some flowers. Anybody got a camellia visible from all sides, and noticed if flowers are evenly distributed? Maybe it's our neighbors who'll benefit from this move!