Anyone use an EF 300mm f4.0 L IS lense ?

Very interested to hear how you get on using this lense for motorsport.

I've been dreaming of the 300mm f2.8 L IS lense, but just can't justify the price, so the next obvious choice is the 300mm f4 L IS

I am likely to use this with a 1.4 extender too ...

Used to use the Nikon version, and we had a Canon one for a couple of weeks too when one of our 2.8s died. Good lens.

I'd like the 2.8 as well but I'm not in the position to spend that sort of money. I've had the f4 for several years now and have mainly used it for motorsport and I'm more than happy with it. I also regularly use it with a 1.4x, here are a couple of examples from the weekend:

Without 1.4x

^ great shots.

IQ is excellent with the 1.4x. Have you tried it with a 2.0x? Also, do you keep the IS on or off?

oooh very nice ...

Can't decide ... 300 F4 IS L or 400 F5.6 L ...

Do you ever find the AF is a little slow ? People tell me the 2.8's AF is awesome ... I'm sure the F4's is still very acceptable ..

Do you mainly shoot it wide open ? If so are you pleased with the results ?

Eric, I've never tried the 2x but from what I've read it seems to make image quality suffer over the 1.4x. I use IS set to No 2 for Motorsport.

Fashioneyes, The AF to me is excellent but then I haven't tried a 2.8, I think at the time I got the 300mm I has a Sigma 150 - 500 and the difference was night and day. As for using it wide open I try to shot cars at around f8 but I've never found it an issue shooting wide open.

Thanks for the reply ... I have the Sigma 150-500 too and am looking for something with more quality ... so I'm thinking the 300 f4 (I already have the 1.4 extender) so will loose a litte reach hence considering the 300 and 400 ...

Yes the 2.8 version is a great lens, but so is the f/4 version. In real terms, there is not much between them in terms of image and build quality, and with the decent ISO noise control in the latest camera bodies that f/4 is very usuable, even in lower light conditions...a lot better than when we were stuck using 100 ISO film emulsions!

The AF of the 300mm f/4 IS does slow down considerably with the use of an extender - at least on my 7D. The 300 plus 1.4 is slower in acquiring focus than the 100-400 at 400 without extender. The IQ on the other hand is outstanding, even with the 1.4. Mine needed some MA when used with the extender.

I wish you guys/girls wouldn't post topics like this. It makes me want to justify the 300 f/4. Ugh! More saving!

Even more confused now ... EF 300mm f2.8 L (non-IS) ... £1,999, 6 months warranty ... is this good considering it cannot be repaired by Canon if anything fails ?

Too bad you're over the pond, I have a 300 f4 for $950

fashioneyes wrote in post #10287080
Even more confused now ... EF 300mm f2.8 L (non-IS) ... £1,999, 6 months warranty ... is this good considering it cannot be repaired by Canon if anything fails ?

camerapricebuster.com is your friend. Best price £1048

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