Most of the time, in the world of bird and wildlife photography, you want the longest telephoto lens you can find. The new M.Zuiko 100-400mm F5.0-6.3 IS lens has an effective focal length of 200-800mm in a relatively compact, affordable form factor. If you add the MC-14 1.4X Teleconverter to the 100-400mm lens, you get a lens with an EFL of 1120mm. If you add the MC-20 2X Teleconverter you get all the way to 1600mm EFL.

Now THAT will get you lots of pixels on any creature that might come into your viewfinder, even if it is far away.

The promise of a new telephoto zoom from Olympus that can achieve that kind of reach has excited many bird and wildlife photographers, including me. I was fortunate enough to get to test the lens early. I have had a couple of outings with this lens and I have to say, it exceeded my hopes. I put it through its paces, using it in real world, professional bird photography situations. 

Eagle Owl
OM-D E-M1 Mark III | M.Zuiko Digital ED 100-400mm F5.0–6.3 IS | MC-14
1/800s | F9 | ISO 400
OM-D E-M1 Mark III | M.Zuiko Digital ED 100-400mm F5.0-6.3 IS
307mm | 1/1000s | F8 | ISO 250

I have used lenses in this focal range throughout my career. I have used most of the commercially available tele-zooms sold in the USA over the last 25 years. NOTHING in this price range and focal length comes close to the quality of the new 100-400mm F5.0-6.3 IS. Nothing.

Let’s start with the basic lens construction and then go on to handling. The 100-400mm is built with four ED lenses for suppressing color bleeding, two Super HR lenses, and two HR lenses for bright, clear, image performance all the way to the edges of the image, and across the entire zoom range. It has the famous ZERO (Zuiko Extra-low Reflection Optical) coating which in my tests, is effectively used to reduce ghosting and flaring. It’s very sturdy and hefty and well built, but it doesn’t feel as heavy as a lens capable of delivering an EFL of 800mm should be.

The rear focus system of the 100-400mm drives the lightweight focusing lenses for fast, high-precision AF performance. This lens is also equipped with a Focus Limiter. It allows switching the AF operating range between three levels according to the focusing distance for quick focusing and comfortable shooting even in the super-telephoto range. Also, the in-lens image stabilization featuring up to three stops of compensation and it actually enables handheld super-telephoto shooting.

This lens has a variable aperture meaning the further you extend the lens, the smaller the maximum aperture will be. Extended to 400mm (800 EFL) your aperture will be F6.3 wide open. You’ll notice that the M.Zuiko 300 F4 IS PRO is faster at F4, but it is also shorter and much more expensive.

OM-D E-M1X | M.Zuiko Digital ED 100-400mm F5.0-6.3 IS
400mm | 1/500s | F6.3 | ISO 200
OM-D E-M1X | M.Zuiko Digital ED 100-400mm F5.0-6.3 IS
1/200s | F11.5 | ISO 500
In the field I found that the lens still delivered a pleasing bokeh because I was able to get close to the subjects. In fact, the close focusing distance on this lens is just four feet and four inches (1.3 meters.) That is simply astounding. To be able to get that close to your subject and still access autofocus is something I consider to be quite remarkable. Similarly situated lenses on DSLRs have minimum close focusing distances of 15 feet and even more.

Since the closer the distance between camera and subject, the shallower the depth-of-field, I was able to work at f/13 and still have a background that was pleasingly out of focus.

There are a couple of handling things I want to mention. Thankfully, Olympus built the lens collar with an Arca-Swiss compatible lens foot. This means you do not need a separate lens plate to mount this lens to any traditional Arca-Swiss compatible ball head or gimbal. This is the same as on the 300 F4 IS PRO lens and I love it. This means one less piece of equipment to buy, carry around and mess with. You can just mount this lens as is to any Arca-Swiss head.

As mentioned, this lens comes with a focus limiter switch. This allows you to speed up autofocus acquisition when photographing subjects that are 1.3 to six meters, or six meters to infinity.

Red Nape
OM-D E-M1 Mark III | M.Zuiko Digital ED 100-400mm F5.0-6.3 IS | MC-14
473mm | 1/640s | F9 | ISO 320
OM-D E-M1 Mark III | M.Zuiko Digital ED 100-400mm F5.0-6.3 IS
138mm | 1/1250s | F5.6 | ISO 250

When working with subjects that are more distant to the camera, this limit really helps. There are other Olympus lenses with this feature, but on the 100-400mm it’s one I strongly recommend that photographers be more inclined to use. The 100-400mm does take a little longer to acquire focus of subjects more than six meters away if the focus limiter switch isn’t selected. But it’s there, so why not use it? I found it to be very effective.

Since some people have already asked me, the new 100-400mm lens does indeed come with a lens hood.Good news: it will also fit the 40-150mm F2.8 PRO.

Lastly, and this is the exciting news, the 100-400mm works with both of Olympus’ teleconverters – the MC-14 and MC-20. This gives you a maximum effective focal length of 1120mm and 1600mm respectively! I don’t think there are many lenses (for any camera system) capable of this kind of reach. While these distances present new opportunity, they also present new challenges. You will need to be careful about atmospheric distortion when working at 1600mm and your technique has to be very good to coax the best results out of this combo. But those are good problems to have.

1600mm! Come on, man. That is far out! (See what I did there?)

I tested both Olympus teleconverters on the 100-400mm and found that both performed beautifully. Some of the pictures that accompany this article were shot using the teleconverters. The results are sharp, and the image quality really very good, especially given the price point of this lens.

OM-D E-M1 Mark III | M.Zuiko Digital ED 100-400 F5.0-6.3 IS
1/600s | F6.3


I have been able to get professional results out of almost every Olympus lens I have ever used. But I have never been able to so EASILY get professional results out of a “prosumer” lens from Olympus or anyone else as I have with the new 100-400mm. 


Scott Bourne is a professional wildlife photographer, author and lecturer who specializes in birds. He was one of the founders of “This Week In Photo”, founder of “”, and is co-founder of the new “Photo Podcast Network” ( He’s been involved with photography for more than four decades and his work has appeared in more than 200 publications.



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