[jho]

I am having a dilemma in choosing between these three lenses. I already have a Canon EF 70-200 f2.8 and 1.4 Canon extender and would like a bit more reach in photographing birds and other wildlife, mainly small mammals such as fox and mink, and ocean wildlife like seals. The dream would be having the Canon EF 500 f4 but in order to afford this I would have to sell a kidney or two or win the lottery.



I am leaning towards the 400 mm f5.6 and would like someone to reassure me I am making the right choice. I hve considered both the Sigma 150-500 and the 50-500 but I don't like the reviews on them going soft at the long end so I thought I would be better off with a crisp 400 mm image than a 500 mm soft one.



I also considered adding a 2x extender to the 70-200 but according the comparison charts on the-digital-picture.com that is more of an emergency option, it will give you a 400mm image but not a very good one.



So please, can you give me some practical advice on this.



the way I argued this in my head.

* The 400 mm f5.6 would give me the best image at 400mm and an option to get good images at 560 with stationary subjects.



* The 300 f4 would give me the best at 300mm and good at 420mm with the extender and ok images with stationary subjects at 600 with a 2x extender, and better low light options with f4 and IS.



* The 100-400 would give me flexibilty and good image quality at all focal lengths, but not the sharpest.





HELP.



Best regards, Jonas.