There have been countless threads of the "100-400 vs. 400 f/5.6" type all over the internet photography fora. The sharpness debate is probably the most popular one.
Typically the 100-400 owners like their 100-400, the 400 f/5.6 owners like their prime lens best. What else is new.

However, there is also a rather commonly held notion that the prime is better for photographing fast action such as running animals or birds in flight. A few, but not all, 100-400 owners do acknowledge that their lens is sluggish to focus.

That is what I'd like to explore in some detail here: the agility of 100-400 lens.
How good have you found the lens for tracking fast objects, be that animals, birds, fast vehicles, sports and such ?

As usual, first hand experience based input is hoped for. Those folks who have used the 100-400 for fast action successfully might wish to include some photo examples........that would be quite helpful.

Uhhh...no offense but how exactly is the above image portraying a fast subject? It doesn't speak anything to the 100-400's AF let alone AF at all. Anyhow, in reference to the thread here are a few I shot with my 100-400+1.4x TC. Keep in mind I do not shoot a lot of fast action with this lens, so what you see it pretty much the only quick action I've captured with it in as many attempts. Also keep in mind that the subject, even though it was shot with a TC attached, was shot against a clear blue sky which makes it that much easier for the lens to track it. I've done some little league baseball as well, but I've yet to upload it to flickr.

Nice black crowned night heron.

It would probably be most useful if people who've owned and used both lenses would offer their opinion. You could do fast action with manual focus with enough time, effort, lost shots and luck, but it really doesn't say much about the alternative.

Great input, Matt, thanx.

Here's a couple from last year's Indy 500. It was practice on fast Friday so they were pretty quick. The lens focused great. Can't say much about the photog however.

Thanks, Pingflood and anytime, Peter

Out of curiosity, Peter, have you shot with the 100-400 at all? If so what were your personal findings--specifically when compared to the 400/5.6? The only reason I ask is because you seem to be an exception to the rule in that your ability to use nearly any lens for PIF's and do so successfully, regardless of the lenses AF speed. It makes me think that technique in such situations outweighs AF performance almost entirely.

Matt, I do not wanna spoil the feedback with my experience yet because I haven't used the 100-400 for action recently. These days I like to use it for stationary targets/scenes and I am very pleased with its performance.

I've been pretty happy with my 100-400 for girls soccer or boys baseball:

In the daylight, my 100-400 worked well for sports -- and I was sometimes even afforded the luxury of stopping down a bit, if the light was bright enough. Although I must admit, most of my sports photography is indoors or under night lights, so I rarely used the 100-400...so infrequently that I just sold it today on the B/S board . We'll see if I miss it.

Here's one with the 30D:

Mine (100-400) seems to get the job done. This was the very first time I found out what it was capable of, on a 1Dmk2n.



and the crop that had me sold on it.

msalvetti wrote:
It's a great airshow lens:

The "NAVY" shot....Where were you able to get that perfect of a shot? Were you on the ground or in the air? Beautiful shot. Thanks for sharing...

Not the fastest targets but that 100-400 works wonders for me:

Looks like one of those military hardware posters.

Here's mine. My problem tracking a BIF is not the AF, it's my skill keeping the bird in the frame.

This is turning out very good, guys.
Especially the images posted might help some of us to rethink a bit our use of the 100-400 lens.

reno.peterson wrote:
The "NAVY" shot....Where were you able to get that perfect of a shot? Were you on the ground or in the air? Beautiful shot. Thanks for sharing...

Thanks guys. I wish I was in the air. That was last weekend, at the RI Airshow. Just happened to have a perfectly-placed cloud bank. Here's another:

I've got way too many to post but I've shot motorsport including rallies, V8 Supercars etc along with Aussie Rules (AFL) football, soccer, tennis, cycling, rugby league, wrestling, motocross, air shows plus heaps of other sports, plus stuff like rock concerts etc all with the 100-400 and in different lighting (day, night, artificial) conditions.
I don't regret at all having bought it. It's a great lens indeed.
Go to www.freewebs.com/philwillmedia/apps/photos to see my photo gallery.
Most of the images up until March of this year (2009) were taken with that lens.
From August 2004 until late 2007 it was coupled to a 10D. In late 2007 I bought a 1D MkII and used it with that until March this year when I bought a 70-200/2.8 and 300/2.8 with 2X and 1.4X extenders and have been using those most of the time but still have the 100-400 and have no intention of getting rid of it.

Very nice pictures, one and all... almost makes me rethink my decision to get a 300 f4 instead of a 100-400.

There's no denying the zoominess of the 100-400. The split second you need 380mm instead of 400mm, that zoom is going to be worth it's weight in gold.

heres on portland or airshow
30D/100-400
my first ever shooting

EF 100-400mm f/4.5-5.6 L IS on a EOS 5D or EOS 5DII. Yes, you can do "action photography" with a 5D class camera.

100-400mm on a 1DMk3. The gull is shot with a x1.4TC, the dog is the bare lens. I prefer the 400 f/5.6 for BIF shots, but the zoom is indispensable for framing shots such as a dog running towards you (this one was at 170mm).

Colin

These are all with the 40D.

You guys know how small and fast-flying Puffins are, right?





And that jetskis fairly zip around?











They're not great jetski shots, but they're sharp and in focus...

There's a whole lot of crap written about what the 100-400mm and xxD bodies "can't" do.

The prime is faster focusing, but the 100-400mm will acquit itself very well if you put the effort in: I was shoulder-to-shoulder with friends using 1D bodies and 300mm f/2.8s or 500mm f/4s when I shot those Puffins, and while they might have got one or two more good images than me, they didn't get anything noticeably better...

I took the photos below over 3 years ago with the 100-400/1DMkIIN combo.
That was my first 100-400 copy and of average sharpness.
It was a bit of a struggle to get those images, especially once focus was lost there was no chance of recovery within the short time window of opportunity.
At that time I did try 300 f/4 IS and 400 f/5.6 IS, and both lenses were a bit better at focusing speed.
All I can say is that 100-400 can obviously do the job, and in those instances where zooming action is required the lens becomes just about the only option.
However, if I wanna maximize my chances of getting a PIF or a DIF shot these days, I invariably take 400 f/5.6 or one of the 200mm or 300mm fast primes.

For action photography I enjoyed a real step up in performance from my 100-400 when I traded the 20D for a 1D2. I give the 400 F4 prime the edge for AF speed and it out resolves the zoom.

That said the zoom performs very well in decent light and I use it without hesitation when 400mm is not wide enough.

Example