In the next few months im thinking off buying a new lens(canon) it will be used mainly for taking (birds in flight shots), and have been looking at 2 fixed focal lenses.

canon ef 400mm f/5.6L usm
canon ef 300mm f/4L is usm
I know that the 300mm has image stabaliser but have been looking at some sites and the say you dont need it for flight shots as to having a high shutterspeed, while the 300mm would be a bit faster in focusing.

so looking for a bit of advice

Andy.

I don't have a Canon so can't really offer much of an opinion but doing a search I came up with these two lenses.

Canon EF Telephoto lens - 400 mm - F/2.8 - Canon EF

Canon Telephoto lens - 400 mm - F/2.8 - Canon EF

Other than the weight and the price how big a difference is there between them?

I noticed the one you were looking at is an F/5.6 hence the question as the faster lens would be better in low light.

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Sandy
Carried it in full, then carry it out empty.

Sandy the 400mm f/2.8 comes in at over £5000, would love to have one but cant aford that
the two i have been looking at , could get them for about £900.
and as you say the 300 f4 would let in a bit more light.

weight wise doesnt realy bother me too much

thanks
Andy.

Sandy,

I have the Nikon equivalent - 2.8 400mm. It is unusable except from a hide, it's just too heavy and absolutely enormous. I'm glad I've got it on long term loan rather than wasted £6k. It's a big penalty for a couple of stops and not worth it for me.

The 300mm f4 on the other hand is just as sharp in normal use even when I add a 1.4TC giving a 420mm f5.6.

I imagine the same will be true for the Canons.

Thanks endrick, im using a sigma 150-500 at the moment and its a lump but can hand hold it, but out the other day it just couldnt keep up due to bad light on the red kites swooping everywhere,

my thoughts are on the 300mm at the moment

thanks
Andy.

If it were me I'd probably opt for the faster 300mm Andy. My brother-in-law uses this exact same lens for photographing military Jets as they fly down the Mach Loop at Cad West. Cracking shots with it.

The question I was asking was what was the difference between the two lenses in the links I put up. One is £140-£230 the other one is £5,739 both appear to be similar lenses and at F/2.8 faster than the ones you are looking at.

__________________
Don't worry, be happy.
Sandy
Carried it in full, then carry it out empty.

Sandy,

It's an error in the page. The links all point to the all-purpose Canon 4.5-5.6 55-200mm

Thats my thoughts also stuart,
though would this lens still auto focus if using a 1.4 tel/converter

thanks Andy

Just my .02 cents here only, but once you get over 300mm ... what have you really gained? Well re-phrase that; tracking a moving object is hard enough, with 'mega-magnification' lens it gets really interesting.

Stationary objects (bird on a post) the really high power lens on a tripod can produce some out standing photographs.

fae

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