[davetee]

Thanks Rog. Yes I've been looking around those two forums..still deliberating though. I upgraded my PC to a Quad Core recently and it has 8GB of Ram, plus a caddy for hot-swapping Hard Drives, for archiving, hopefully that will do the trick.

The EX3 has a factor of 5 so the 150-500 would give me 750-2500 which should still be enough. I agree...I would definitely sort some kind of rail system out.

MTF may be making a Canon to EX3 adaptor which Manually controls the aperture...if that happens I'll probably go for the EX3 so I can use my Canon glass...and use the Sigma with my DSLR.

Thanks fore your input.

Dave