I have a similar clearance problem when using my Manfrotto (Bogen in the US) 3299 QR base (the small, almost square RC2 system) with a 3157N QR plate on the tripod mount of a certain type of 80-200/2.8L lens with an undefined brand of 8.2 Mpx camera. The thumb lever on the QR base collides with the front of the camera's battery grip, when the grip is installed. I get around this by simply turning the QR plate backwards on the lens tripod mount. The thumb lever and safety mini-lever on the QR base are now at the front of the assembly (i.e. towards where the lens is pointed), instead of their normal position at the back. I do this with the Manfrotto ball head (i.e. joystick) on my monopod, and with the 352 medium ball head on my tripod.
For my SMC Pentax 500/4.5 on a tripod, I use the same Manfrotto 3421 heavy duty gimbal head as described by Tom, except not in the same way as shown in the picture at the link Tom provided. I use it with the centre yoke down (not up as in the pic), which makes much more sense from a purely physics-based analysis of stability. I sometimes also use the Manfrotto 3252 Long Lens support, especially when I have a teleconverter or two on the 500/4.5, but it is a very stiff system which requires mirror lock up for decent results (hence the undisclosed brand of 8.2 Mpx camera). More often, I use a handheld 300/4L IS on a 1.6 cropping factor 8.2 Mpx camera (equivalent to 480mm, or 672mm with a 1.4X extender)... oh wait, sorry, I probably shouldn't have said "IS", as we're not supposed to talk about that kind of stuff here. Jim www.jcolwell.ca

