Canon's 100-400 zooms

When I bought into Canon, the EOS system had existed for many years.  I used a bonus and started with a 20D (which struck me as already better than 35mm film) and the 70-200 f/2.8L IS.  I later added a used 300mm f/4L and a 1.4x teleconverter.   At the time, I lived near Huntley Meadows, a wetlands near Alexandria, VA, which has some amazing wildlife (if you find yourself in the area, I highly recommend you go).  But I found that no matter which lens I had at the ready, it was the wrong one.  If I had the 70-200 mounted, of course I wanted more reach.  If I had the 300+1.4x, I'd inevitably turn a corner and find I was too close.  Both of those lenses were great, but I realized I really wanted the 100-400 for my use.

I had a brief overlap, and found my copy of the 100-400 was easily on par with the 70-200L and the 300L + 1.4x at respective lengths, and so I gave up the speed for the range I really needed.  It was just about perfect for my needs.  My biggest gripe was the minimum focus distance of about 1.8m.  I can't tell you how many times I tried to get close to a frog only to have to take a step back.  The other gripe was iffy bokeh.  It was fine in most cases but could sometimes show a nervousness that I don't like.

Originally, I avoided the first 100-400L because of several reports that it was soft.  After some time however, I read of more and more reports where it was quite sharp; on par with the rest of the L lenses.  Mine was quite sharp.  I found the resolution at 100mm on par with my 100 USM macro, albeit with lower contrast (making it seem less sharp).

Some people complained about the push-pull zoom design, but coming from older Minolta manual zooms, I was used to that design.

I never saw it collect dust inside (some people call it the dust pump).

I never tested corner sharpness because I found that 99% of the time, the corners were out of focus anyway and just didn't matter.

Here are some images from the original Canon 100-400L:

The original model was very sharp, focused reasonably quickly, had useful IS, etc

Nice detail and contrast from the original Canon 100-400

So when the 100-400 II finally arrived, I wasn't very interested... until I learned about the much closer minimum focus distance (1m!).  I knew it would be useful for me.  As I researched the lens, I learned it was much sharper with better contrast, has better AF speed, works well with the latest teleconverters, has better stabilization, better bokeh... in short the new model is better in most ways.  Most of those improvements didn't matter to me, honestly, but again the short 1 meter MFD is wonderful.

So I saved my pennies and sold the original and finally bought the mark II.  It's worth it, but it isn't perfect.  I've seen some purple fringing even in the center with certain high contrast images. I wish the lens collar was removable, and, as I was happy with the push-pull zoom, I wish they'd kept that design.  Those are just nitpicks.  I'm super happy with the results, and I adapted to the new zoom ring.

The improved stabilization is great.  One of my first hand-held test shots was done at 400mm and 1/15s and it was perfectly sharp.  That was a static subject of course.  And your results will vary depending on your caffeine level.

My only big gripe with the 100-400 II is the swirly bokeh that can happen in some images.  It doesn't bother everyone but it definitely distracts me from the subject when I see it.

Here are some samples from the Canon 100-400L mark II:

Canon 100-400 II, showing a bit of swirly bokeh

Wonderful detail and contrast from the 100-400 II

It makes a great landscape lens too

I considered some other options such as the 400L, a Tamron 150-600, the Sigma 150-600, etc, but nothing has the MFD or portability of the 100-400 II.

If you shoot Canon and need a portable and versatile longer lens, then one of these will easily fit your needs, and fit in your bag.  If you can't afford the mark II, the original is very viable.