I have a Sony, whatever you do don't buy the reflex 500mm fixed lens its hopeless, the lens I see all the time producing extremly good photos is the 150-500mm. The 70-400 is over a £1000 and you can buy a canon 400mm for just over a thousand. I'm regreting buying a Sony because there are too few lens for it even though there are Sigma and Tamron. I like your Sparrow photo its a pity the holder is bright red.