I'm not sure if this is the right place to post this so feel free to move it to a more appropriate forum. That said, I'm looking to try some widefield astrophotography with my Canon XSi piggybacked on my SV102ED/CG5-ASTG combo. Maximun weight with XSi and longest lens is around 6-8 pounds.

I'm looking at a V-Series dovetail bar VDUP-11 to bolt to the top of my SV RS102 rings and a VDPA Vixen Dovetail Plate Adaptor from ADM to mount the ball head on the bar. Or, I suppose it could also be bolted directly to the VDUP-11. ADM also has a V-Series Bogen Camera Mount with a Bogen 3262 Ball Head. It does support up to 8 pounds but I've read that this ball head isn't all that sturdy and suffers from ball head creep. Another advantage of this configuration is that I can also use ADM's guidescope rings to mount a guidescope to the bar if I decide to move onto prime focus later one. All I would need in the rings plus adaptors. Trying to plan ahead as best I can.

I've looked at tons of ball heads from Kirk, AcraTech, Arca Swiss, Markins, RRS, Bogen, Gitzo, Giottos, etc. Most of them are far too expensive and seem like overkill for what I want to do. The two I'm considering at the moment are the Manfrotto 486RC2 and the 488RC2. Both will support the maximum weight adequately, The 488 is half a pound heavier but it has separate pan and tilt locking mechanisms, where the 486 only has one lever for both. Of course the 488 is around $30.00 more than the 486 but well worth if it provides more stability. I can see the camera ending up in some very odd positions depending on the target and more flexibility to frame the object seems like a good thing to me.

So, any thoughts or feedback on this or experience with either of these ball heads (or ADM accessories)? Recommendations for other ball heads/bars/adaptors that might work as well? I won't say that money is no object or spare no expense. However, I'm one of those guys who believes in over-engineering stuff to make sure it doesn't break. Thanks for your help.