10-12-2012, 01:38 PM
I have the 300 f4L IS and the 400 f5.6L. I bought the 400 for shooting birds and BIF but found that where I live (London, UK) 400 is way too short. It also needs lots of light - it may be OK in Florida or California, but not here, though this is becoming less of an issue as the latest SDLRs become better and better at high ISOs. I haven't used it for 2 years so will eBay it shortly. It also won't AF with even a 1.4xTC unless you have a 1D series body. Great lens though, sharp wide open with fast accurate AF, though the long FL means you need very good technique and/or a very sturdy tripod.
The 300 f4 IS is a very sharp lens which has the added advantage of a very short MFD - almost but not quite a macro (the 400 has a very long MFD). The IS is first generation worth only one stop and is very noisy and 'graunchy'. A bit off-putting at first. It works well with a 1.4xTC to give you 420mm equivalent at f5.6, though the AF of this combo is nowhere near as fast as the 400 prime. However, I will probably keep this lens as it gives me 420mm with the TC, though I am also tempted by the newer 70-300L which will enable me to reduce my lens count ( I also have the 70-200 f4L IS).
Also, though the 400 is heavier on the scales, it doesn't feel heavier. It is quite a bit longer than the 300, but the 300 is stubbier and 'stocky' and doesn't balance as well on the camera (I use a 5DII and 40D).
Have never used the 100-400 zoom but the flexibility of a zoom for birds and wildlife should not be under-estimated. The IQ of the latest copies seems to be much improved if the posters on the dpreview forums are to be believed.
Michael
The 300 f4 IS is a very sharp lens which has the added advantage of a very short MFD - almost but not quite a macro (the 400 has a very long MFD). The IS is first generation worth only one stop and is very noisy and 'graunchy'. A bit off-putting at first. It works well with a 1.4xTC to give you 420mm equivalent at f5.6, though the AF of this combo is nowhere near as fast as the 400 prime. However, I will probably keep this lens as it gives me 420mm with the TC, though I am also tempted by the newer 70-300L which will enable me to reduce my lens count ( I also have the 70-200 f4L IS).
Also, though the 400 is heavier on the scales, it doesn't feel heavier. It is quite a bit longer than the 300, but the 300 is stubbier and 'stocky' and doesn't balance as well on the camera (I use a 5DII and 40D).
Have never used the 100-400 zoom but the flexibility of a zoom for birds and wildlife should not be under-estimated. The IQ of the latest copies seems to be much improved if the posters on the dpreview forums are to be believed.
Michael