Canon EF400mm f5.6 versus Canon EF100-400mm f4.5-f5.6

[John27]

Hi folks

Having attended the MotoGP at Valalencia last week, and using my 7d with a 70-200mm with 1.4 extender. I have realised I need a longer lens for such events.  I was wondering what lens would be better, ie sharpness.  I know the 100-400mm has the benefit of the zoom, but I don't want to lose image quality if I can help it. 

John

[diverhank]

For Canon, all of the super telephotos - the ones that cost $14,000 - are primes...so the pro sports shooters and the pro BIF shooters don't seem to need zooms to ply their trades...So I don't buy your argument regarding not getting the shots using the 400mm f/5.6. 

It's fine to use your 100-400, nothing wrong with that lens but don't try to say the 400mm is not useful.  The internet is full of incredible pictures taken by this lens.  Perhaps it needs to be in the right hands.  Search the internet for picture comparisons...the gain in sharpness is significant, not just a little like many are saying here.

[Michaeldigital]

"

It's fine to use your 100-400, nothing wrong with that lens but don't try to say the 400mm is not useful.  The internet is full of incredible pictures taken by this lens.  Perhaps it needs to be in the right hands.  Search the internet for picture comparisons...the gain in sharpness is significant, not just a little like many are saying here."

Another very important factor of the 400L ƒ5.6 is the much faster acquistion of focus vs. the 100/400L making it a much better lens for birds in flight and other moving objects

400L ƒ5.6 manual exposure 1/1600 @ ƒ8 handheld