I just did some research into the newly announced Canon long lenses - weight is my only concern right now. Prices will give me a heat attack I am sure, but that will be later. I only handhold my EF 500/4 and consider the Sigmonster (300-800/5.6) as a tripod only lens. The new lenses are very much lighter and open up some new possibilities, especially when you consider better IS performance.
NEW Present version
EF 400/2.8 II 8.49 LB 11.7 LB
EF 500/4 II 7 LB 8.53 LB
EF 600/4 II 8.6 LB 11.8 LB
EF 800/5.6 9.9 LB
Sigma 300-800/5.6 12.9 LB
Nothing shorter is on my radar now. Looks like I could manage the new 600 as it is weight wise near the present 500. What is not here is the length of the lens. Makes a huge difference as well. With most of the weight at the front of the lens where the big glass is, balance becomes an issue, not just overall weight. Since the 600/4 is longer than the 500/4, might make all the difference.




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