Next on my list of equipment to purchase, I think, may well be a macro set up. I do like those really detailed shots on here. I have a D90, 18-105 kit lens, a Sigma 10-20, and a 70-300 VR2 Nikkor, I have around £400 to spend. What would you recommend? Macro lens, teleconverters, or extension tubes? I believe I can't use TC's on the 70-300.