EF 100-400 and EF 300 f/4

I am not using the 100-400 as much and I want to buy the Canon EF 300 f/4
Is the 300 f/4 more sharp and faster than 100-400 at 400mm?

Thanks a lot:)

The 300f/4IS is a great lens, I used it in low light, as semi-macro with extension tubes because of the minimum focusing distance of 1.4m and with a 1.4xTC at 420mm. Without TC it focuses very quickly, average with TC. For bird photography and BIF in good light, the 400f/5.6 is a great alternative.

There is no comparison. The 300 is much sharper and has a faster AF than the zoom. Works great with a 1.4X converter. Lots of applications.

The 400 5.6 as suggested by Axel would be excellent to complement the 300 f4.0 Don't think it could replace it. It would be used basically without converters, its not a good macro lens and would classify as a flight lens. Again all depends on your application.

Thanks a lot:)

I am very biased, I reckon my 100-400 lens is superb and I wouldn't go 100mm shorter and without flexibility for an extra stop of light. The 300 mm may in theory be sharper but if you keep that zoom lens still and you have reasonably good PS skills you won't be disappointed. I am a very strong believer that most L lenses out-perform many of their owners (including me) and the biggest source of performance deficiency is operator error - this equally applies to me!
Don't get me wrong the 300mm is a great lens but I personally think you will not see much difference in quality at 300mm, I am sure there is a difference at bench testing level but in practical terms I very much doubt it. Have you seen Arty's shots with the 100-400 - hey some are even better than mine! (Only kidding Art)
I have recently bought the 500mm but I certainly wouldn't buy the 300mm, that is my biased view, it is biased because I get great results with the 100-400mm lens.
Jon

Thanks Jon!

From my experience of using the 300 f4 Is, 100-400, 400f5.6, 70-200f2.8 with 2xTc, I would rate the 300 F4 L IS USM lens as the sharpest.

I find the 300 F4 is fantastic and very sharp even at f4. I have shot a lot of shots at f4 and am happy with it. I have used it with a 1.4x Tc and find the results sharp at f5.6. This combo beats the 100-400f5.6 at f5.6 in terms of sharpness and also beats the 70-200 with 2x at f5.6 at 400mm.

I'll add my vote for the 300 f/4 IS. I have the 100-400 and so do friends. The 100-400 seems to have variablilty in quality. A friend's 100-400 is quite sharp at 400, but mine is not. It is NOT due to technique. It demonstrable on tripod with mirror lockup with both the 300 and 100-400. The other issue with the 100-400 is it is not a sealed lens, so air pumps in and out as you zoom, and along with air comes dust. I replaced my 100-400 with a 300 f/4 IS. The 300 is lighter and works well with 1.4x and 2x (on 1D Bodies) TCs. If you really want the 100-400, fully test the one you will get, and if it is not sharp at 400, give it back. By unsharp, I mean it makes OK 8x10 prints, but not tack sharp.
If you want to buy my 100-400, drop me a line ;-).

This is an example of the 100-400 at 400 (on 35mm Velvia):
http://www.clarkvision.com/galleries...baby.goat.html
I think you can tell the image is OK, but not critically sharp.

And this is the 300 f/4 + 1.4x TC, and is very sharp:
http://www.clarkvision.com/galleries...962.b-700.html

Gotta go test my 300 f/2.8 IS I just got....

Roger
http://www.clarkvision.com