My (very) limited experience moving from the 400 5.6 to the 100-400 II indicates that getting good shots with the new lens will be much easier in most circumstances compared to the 400. As to sharpness, the 100-400 II appears to be at least equal to the 400, and the outstanding IS functionally results in better sharpness in a lot of real-world shooting situations.
So true, The 100-400LII is such a fantastic lens,.. if the 400mm 5.6 is a 10 out of 10 ...the 100-400LII is a 15 out of 10 no doubt'
Al do not rent this lens unless you have the cash to keep it lol
I came from both. I liked the 100-400mm mkI for it's flexibility, it's lightning fast push pull zoom.
However, I also shot a lot with the 400mm f/5.6L prime for it's faster AF, and superior image quality. It's limitations in lack of IS, no zoom and terrible MFD were balanced by it's amazing performance in AF and IQ that rivaled lenses costing 8 to 10 times as much.
From the gut, I liked the prime more. It felt better to shoot, and the images stood out.
From a utility stand point, the zoom remained my "swiss army knife" of wildlife lens.
With the purchase of the 100-400mm MkII I quickly learned that my need for the prime as well as the zoom was gone,. The MkII's AF is faster than the old prime, and it's IQ seems to be equal to the prime at all focal lengths.
If I had reason to keep the prime, I would. But look at the resales of the 400mm prime and you'll see that no one is keeping it once they get there hands on the new zoom.
FYI, I go into a bit more detail on the first page of this thread if you are interested.
I went from the 400 f/5.6 to the 100-400L II as I really struggled with the 400mm. The IS on the new zoom was a game changer for me. The light in the north of Scotland is pretty poor most of the year and even with high ISO I couldn't use a fast enough shutter speed except on exceptionally bright days. When I got the 100-400II I was taking hand-held images at 1/15 second. For BIF, of course, it's not such a major difference as you need the faster SS anyway.
You guys are killing me.
Pondrader, I know I am going to like it as the images I am seeing have been outstanding, but I have to test it to see for myself and if it's as good as everyone is saying it is, then I have some decisions to make. I found myself in a situation just this past Saturday (out with the X Country team in the woods) saying man I wish I had the 100-400 now as I saw lots of dear; that was the ideal situation to have that zoom. I am going to get the loaner from CPS within the next couple weeks.
CyberDyneSystems, when I saw the minimum focusing distance I coughed/choked. It is something that I love on my 300 f4 IS. That and IS is becoming prime reasons for my lens purchasing decisions these days - nothing more frustrating to have an image opportunity that gets to close and you have to or can't back up. I figured the image quality would be on par with the prime, which used to be my 2nd lens out on shoots.
stsva and AnnieMacD that is what I have been reading - IS is the game changer. I hand held the 5.6 a lot, but also used it mostly on a tridpod and a Jobu Jr. to get solid shots. I do find myself relying more on IS these days, especially in bad lighting situations, so IS is always welcomed.
I kind of already know how this is going to play out - haha!. I may have the 400 5.6 and 1D3 up for sell soom (not quite sure about the 1D3 though).
Thanks everyone for the insight...Al