Sigma 50-500 OS vs Canon 100-400 IS

[dulvariprestige]

I agree with benny with the push-pull zoom, takes a little to get used to, but once you do, it feels really natural, plus when you're hand holding you're supporting at the front of the lens, which I think gives you much better stability.

I do miss this lens.

[neil70]

i use the 100-400 for sport (motox and aussie rules). i feel that it is a grate lens. the push pull zoom feels more natural when following or paning than a twist zoom

[ram63]

For what it is worth I have the Sigma 50-500 and I have taken some lovely shots with it (in my humble opinion) it does hunt a little in poor contrast conditions, but I am sure that most lenses will do that from time to time.
I use it on a Manfroto mono pod with my Pentax K10d and usually sit in quiet observation so the weight is not normally noticeable, but watch out if you point the lens down it will fully extend if you have not locked it.
I have also used it hand held with the carry handle as a balance point with some good results.
I am only new to photography but I do love my "BIGMA"
Good luck with whatever lens you choose it is great to be able to reach out to your subject and also very handy to bring your lens back to capture something happening right under your nose

[peterb666]

One thing that puzzles me about this thread is why are people comparing a 4x zoom to a 10x zoom?

[ving]

Definitely "or something".

There are lenses which can actually meter and focus at f/5. In fact, there is a special term for this sort of lens. It is called "an f/5 lens".

If it was possible to meter at f/5, it would be equally possible to shoot at f/5. What Mr Not-Kym (Mr Not-Kym 'cause I don't reckon Mr Kym would have got this one wrong) was presumably thinking of is modern focusing and metering where the shooting aperture is smaller than the maximum aperture. If, for example, you are shooting at f/11 with a 24-105/4 lens, what you see through the viewfinder is the f/4 view; what the camera meters with is the f/4 view (it does the sums from there to work out what exposure is required at f/11); and what the focus system focuses with is the f/4 view. The camera is smart enough to leave the lens wide open all the time except for the last moment before the shutter fires (which you can't see anyway because the mirror has already flipped). The only time you ever see the stopped-down view is when you press the DOF preview button.

This applies to the Sigma the same as it applies to every other lens ever made. (Er ... sorry ... before about 1970 cameras and lenses were fully manual. You had to do everything, including manually turning the aperture ring to dial up f/11 or whatever you wanted.) I'll try again ....

This applies to the Sigma the same as it applies to every other lens made since about 1970. Regardless of the aperture you are going to shoot at, the cameras focuses at the maximum aperture available to it with the lens and focal length selected. In the case of the Sigma, that's f/6.3. You get f/6.3 "leverage" which is a bit less than f/5.6 "leverage" and a huge amount lefs than f/4 or f/2.8 "leverage". (They don't call fast lenses "fast" for nothing!)

So:

Pro Sigma: 100mm longer.
Pro Canon: faster, better focus, much lighter, possibly better quality.

I have no doubt that the Sigma is a fine lens, and wouldn't be upset to see you buy one. My leaning, as I said, is to the Canon, but only by a small margin. They are both good choices.

Enjoy!

ahh! i see. thanks for the explanation....

so if a camera cant focus at any higher that f5.6 then the sigma lens wont focus at 500mm (or whenever the siggy goes above 5.6)?

just as well i got a nikon, it focuses at f6.3


...or am i even more confused now

[Riverlander]

...or am i even more confused now

Well, if you are not confused David, I am.
My new Sigma 50-500 focuses at 500 mm very quickly and accurately! I love it.

[peterb666]

So:

Pro Sigma: 100mm longer.
Pro Canon: faster, better focus, much lighter, possibly better quality.

Both are fine lenses. I have the Sigma 150-500mm zoom and it has no problem focussing on a Nikon body so maybe there is an issue with the Canon AF system. I don't know. Certainly Nikon don't have a restriction of f/5.6 for focussing (well except in the old split prism MF days when the split prism would black out - just like Canon).

The pros and cons list could have done with a little more research.

Pro for the Sigma 50-500mm zoom:
* - 100% wider and the short end. That is quite significant.
* - 20% longer at the long end. While noticeable and worthwhile, it isn't a huge plus.
* - closer focussing distance although that may not be that relevant to most.
* - It costs $800 less than the Canon (typical street prices)

I would hope the Canon would be a better lens as you only get a 4x zoom compared to a 10x zoom, it doesn’t focus as closely and it costs 50% more so it should be a better product within its design limitations. There would be serious issues at Canon if that were not the case. How much better it is in the field is doubtful at the difference in aperture is only around 1/3rd a stop.

According to LenTip whose reviews are quite detailed (although the English translation is sometimes odd), both lenses focus quickly and accurately. In fact very accurately with the Canon missing only around 2% and the Sigma 3%. Both excellent figures and while the Sigma is a whole 1% worse, don't forget the longer focal length range, closer focussing and slower aperture.

Canon 100-400mm review

Sigma 50-500mm review

Check out the lens resolution tests in the above reviews. There is no doubt that the Canon is sharper at f/5.6 at the long end but the Sigma is the same or better at f/8 and smaller apertures depending on the focal length (although both are quite close). If you need depth of field at the longer focal lengths, the Sigma is a good choice. What is also interesting is how good the resolution for the Sigma at the 50mm end. On the other hand, if you shoot wide open, then the advantage is with the Canon.

Now that the crap is out of the way, just go out and buy the best lens for your type of photography and within your budget and stop wasting your time procrastinating.

[Pinarelloman]

I have the Canon 100-400 and it is brilliant.
I cannot comment personally on the Sigma, but a guy at work has one and is not totally happy with it.

[mongo]

There is no doubt that the canon has excellent IQ – difficult to beat and amongst the best in this class of lens. The sigma is not quite up to the canon but sometimes - only just, and other times, in the right hands and conditions it may match the canon.

Mrs Mongo has the latest 50-500 sigma for her Pentax K5 and she gets incredibly sharp results from it. Ironically, she chooses to focus manually despite its AF but this is not because of any problem with the AF (which is very quick and accurate) , its just a preference of hers that is now a habit.

[Tannin]

I have the Sigma 150-500mm zoom and it has no problem focussing on a Nikon body so maybe there is an issue with the Canon AF system. I don't know.

I already explained all that. Maybe I was unclear. Let's try it again.

There is NO DIFFERENCE between brands in the way that autofocus systems respond to max aperture. Zip. Nil. Nada. None.

They all work on the same theory. They all degrade when you present them with a smaller max-aperture lens. Canon prefer to switch off the AF when the performance is likely to be marginal, Nikon prefer to do nothing and hope for the best, but both can be user-overridden if desired.

There MAY be a difference between different models as regards ability to cope with slow lenses, but we have not established that here in this thread, or indeed anywhere that I know of, and I am not aware of any consistent difference between camera brands as opposed to individual camera models.

I seem to recall, for example, that the 40D was marginally more able to cope with an f/8 lens/TC combination than the 20D. (Or possibly it was the other way around.) Be that as it may, the only significant variation seems to be with price and AF system quality. The Canon 1 Series cameras do it better than the XXD or XXXD bodies. (Just as they do nearly everything else better.) In the same way, I would expect a D3 or a D300 to do better than a D40X. Even so, the differences are quite small.

Certainly Nikon don't have a restriction of f/5.6 for focussing (well except in the old split prism MF days when the split prism would black out - just like Canon).

Nikon has EXACTLY THE SAME restriction as Canon. And Pentax. And Olympus. And any other camera that uses a phase detection focus system. Indeed, you have seen this for yourself when watching a split prism black out - for that too is based on the same fundamental working method.

The AF system in your Nikon (exactly the same as the AF system in any other SLR) is staring at a blacker and blacker split prism as you put on slower lenses. It gets slower to focus and hunts more and makes more mistakes. Saying "my Brand Z focuses at f/x.x" doesn't really tell us much at all. I would expect any brand of camera to focus, more or less, most of the time with an f/6.3 lens - but it won't do it as fast and as well as it does with an f/5.6 lens.

The performance degradation is progressive: each half stop is just a little bit worse than the one before. Where do you draw the line and say "this doesn't AF"? Matter of judgment as much as anything else. And also of luck - I have regularly heard quite different reports from people owning the exact same cameras and lenses.

(Usually these are bird people trying to get a bit more reach out of kit that doesn't quite have what it takes - bird photographers, especially beginning bird photographers, are always trying to get more reach than they can afford, and usually wind up going a bridge too far before they back off a bit and start working within the limitations of their equipment instead of crossing them and having a struggle.)

What would be relevant is comparison of focus speed and accuracy between different makes of camera using the same lens. (Though even this could be a bit hit and miss, as none of the camera manufacturers trouble to test and tune their products with 3rd party lenses.)