Canon 100-400 L or Sigma 50-500

[modchild]

Hi guys, which would you go for. I've got a 7D and a 5dMkII and I mostly shoot airplanes and wildlife. I've already got the 100-400 L and have used it regularly on the 7D and for the first time today with the 5DMkII.
Just not sure now that I've got quite enough reach on the 5D though, it worked well enough today in the park shooting birds and squirrels but not sure if it'll be long enough for planes.
I know the IQ of the 100-400 L is great, cant fault it at all, but I'm sure some of you Sigma owners will tell me if the IQ is as good as the 100-400L.

 

[squishy]

IMHO You won't really gain reach from the 50-500. I dare say you could crop files from the 100-400 at full reach a tad to match the 50-500 and the quality would easily be comparable.

From what I've experienced and read the 100-400 is just a whisker sharper than the 50-500, but not a difference you're likely to see in the real world. (that depends who you ask, but I've tried all these lenses and read many, many reviews and come to this conclusion. I know some people on here with experience of both say the 50-500 is sharper, it's probably worth trying one yourself if you're seriously considering swapping, a lot of people disagree on how they compare). But certainly they can both deliver on image quality.

The 100-400 is apparently one of the most popular lenses for airshows, so I'd be very surprised if it wasn't at least adequate. Personally I wouldn't trade for the 50-500 unless it's the 50mm end you need.

Really I'd try and find to try alongside you're 100-400, you're unlikely to get unanimous advice on here so you're best off making your own mind up .

 

[scottthehat]

Have used both and from my experience the 50-500mm os is sharper. But as your happy with the canon have you thought about the new Sigma 120-300 os and a 2x tc.

one thing to add that the os in the sigma is far better then the canon is in the 100-400mm.

 

[draiman]

Would agree that the 50-500 OS is marginally sharper but also heavier. I wouldn't think the 100mm extra would make that much a difference either. Not a worthwhile upgrade.

 

[u8myufo]

Another thread to add to the hundreds of 100-400 v 50-500 already out there :shrug: As you already have one of them Stuart then the obvious thing would be to go and test a Siggy at a shop or see if there is a fellow member near to you who has one you could try. Go back and compare the results. The only other choice you really have is to just go out and buy it Far too many other governing factors to take into consideration when just asking for someones opinion.