Thanks for the comments everyone.


John: thanks for the info on the filter. I noticed you mention this in another thread recently. I'll have a look for sources in the UK.


Joel:thanks for the reply. It's useful info since I've been considering acquiring a 500mm lens when funds permit.


Pat: I agree with Brant (Kayaker) - no need to apologise for your backlog of processing, there's no time limit in this thread.