/me strokes 18-200 VR Nikkor....
Ive a cheap 70-300 pre-digital zoom Nikkor thats fairly pants but does give you equivalent 450mm focal length. Its a bit rubbish wide open though, anything thats good is £££££ at least!
TBH I feel that the horrendous amount of compression and Jpegging on those pics hides any compromise due to high ISOs! The other thing that stands out for me is that the background in many intrudes too much, so youd be be best choosing a position with a more neutral or featureless bit of the scenery behind, or a wider aperture to get less DoF.
Yeah its going to be rather expensive to get anything decent, the 70-300 seems to have done alright but I was probably sitting as close to the wicket as I could, other places around the ground, that might get rid of the busy background was further away. I might need something around the 400mm range, I just need to win the lottery to afford it. As for DoF I just stuck with F8 mainly but having looked at them I could have easily got away with 5.6 the fastest the lense can go at, that should help.
As for the jpegging & compression Ive had to shrink all the images right down and put the watermark on as one of the ideas of the club is to sell these to people, so thats more of a preview album. And its being hosted on my pc at home, so if I put up the full size originals itd kill my connection.
Mongoose, that Sigma 100-300 F4 sounds interesting, just read a review on the net saying it works quite well with a 1.4x teleconverter, might solve a problem of 300mm being a touch too short.