EF 70-200mm f/4L IS USM part2

f/4@1/20th, 200mm

Using the Canon EF 70-200mm f/4L IS USM wide-open...


Back on October 8th, we took a quick look at Canon's EF 70-200mm f/4L IS USM performance and handling overall.

Today, we'll mostly just be taking a look at some examples of that lens shot wide-open (f/4) or thereabouts on a crop-frame sensor.

f/4 @ 1/250th, 200mm
In full-size photo, tread text and even scores on the rotors are easily depicted.

As we saw last time, this lens has the potential for producing some very sharp, very contrasty images. The good news is that changes little when shot at maximum aperture. Visually, and even with some pixel-peeping, this lens performs just as well at f/4 as it does at f/8.

Indeed, lens tests at sites such as Photodo, The Digital Picture and Photozone show only a slight increase in resolution gained by stopping down, and this lens performs easily within the realm of fixed-focus (prime) lenses.

And to sweeten the deal even more, the Bokeh (quality of out-of-focus areas) is arguably very nice - quite smooth and buttery, which is how I like it. Different photographers prefer different Bokeh qualities, but the 70-200 f/4 easily produces my kind of Bokeh, and this on a crop-sensor as well.

If you're not aware, the perceived depth-of-field (DOF) on crop sensors appears deeper - meaning that at any given aperture, more of the background appears to be in focus than it would on a "full-frame" sensor. This is because DOF is partially a quality of image magnification, and on a crop sensor, you might end up being farther from the subject that you would on a larger sensor to get the same cropping. Farther away equals less magnification, therefore more DOF, and more of the background in focus. This is okay if you're looking to have more DOF at similar apertures than larger sensors, but trouble if you're trying to produce dreamy OOF (out of focus) areas in your photos.

Now, the Canon 79-200 f/4 isn't offering any magic to counteract this, its just that at f/4, great Bokeh is still to be had, even though its not a shallow as its more expensive f/2.8 sibling.

Here are some samples to illustrate the wide-open capabilities of this lens:

f/4@1/30th, 116mm
Isolation of this mock-orange from an otherwise busy bkgd.

f/4@125th, 70mm
Tack-sharpness with shallow DOF = easy to isolate subjects

f/5.6@1/60th,  144mm
Even though stopped down to 5.6, the distracting fence in the bkgd
has still been very much diminished.

f/4@1/30th, 200mm
Standing directly over these mushrooms, note how fast the DOF falls off
in just a few inches. Very nice.

f/4@1/20th, 93mm

f/4@1/30th, 200mm
Note that these are handheld at 1/20th and 1/30th sec
The Image Stabilization really works.

f/4@1/20th, 70mm
Lens works with dogs too!