Olympus M.Zuiko 100-400mm/5.0-6.3 IS Review | Petr Bambousek | Wildlife Photography

Olympus M.Zuiko 100-400mm/5.0-6.3 IS

Olympus M.Zuiko 100-400mm/5.0-6.3 IS

04 Aug 2020, Posted by Petr Bambousek in Articles, Equipment, Olympus gear

The first of the two upcoming superzooms for 2020 release from Olympus is M.Zuiko 100-400mm/ 5.0-6.3 IS, which goes on sale in the next few days. Thanks to Olympus CZ & SK, I had the incredible opportunity to test the lens (thank you Olympus CZ & SK for the loan), and here are my first-hand observations. I would like to clarify that the lens I was loaned was a pre-production sample (fw 1.0) and the final results may differ from the actual product.

Ground squirrel, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 400mm, ISO 200, f/6.3, 1/250s, z ruky

About the lens


Despite being a mid-range lens, it boasts a myriad of professional PRO lens range features. At first glance and touch, it features very precise workmanship, an ArcaSwiss profile tripod plate, and absolutely silky-smooth running of the focusing and zoom rings. Both of these are also distinguishable from each other by touch thanks to the ingenious use of different types of non-slip rubber coating. The lens also shares extensive hermetic sealing on the entire lens barrel assuring the same level of dust, splash and freezeproof performance as the PRO series. Anyone who used Olympus lenses against the elements of unpredictable weather knows that these claims are not just plain words, but an actual guarantee of exceptional endurance during any environmental conditions.

Olympus E-M1 II, M.Zuiko 100-400mm/5.0-6.3 IS – weather sealed

In terms of its size and weight, it is almost identical to the legendary M.Zuiko 300mm/ 4 IS. Why legendary? Because that lens is a real gem for wildlife photographers and anyone who had the pleasure to experience its true abilities has high standards relative to other lenses as a result. Optically, probably only two lenses can match its performance – the Panasonic 200mm/ 2.8 OIS, and I assume, quite likely the highly anticipated M.Zuiko 150-400mm/ 4.5 IS with a built-in 1.25x converter. We could hopefully see the latter on sale at the end of 2020.

Mute Swan, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 400mm, ISO 250, f/6.3, 1/1600s, handheld

Image Stabilisation


The M.Zuiko 100-400mm/ 5.0-6.3 IS has, as the name suggests, the image stabilisation mechanism as the 300mm/ 4 IS. So far, this is a third lens with a built-in image stabilisation mechanism (along with a 300mm and a 12-100mm). However, it lacks a precise image stabilisation synchronising with the body. Additionally, I felt that it was slowing down the overall performance of the camera. Consequently, when used with the OM-D E-M1 III body, I preferred to turn the stabilisation on the lens off and prioritise the one built in the body that can handle up to -7 EV compensation. The onset and performance of image stabilisation were then seemingly smoother. The question remains, which image stabilisation will be more swift and expedient on the lower models, such as the E-M10/ E-M5 series. I highly recommend all the new lens owners to experiment with both mechanisms to see, which will bring them better results.

Olympus M.Zuiko 100-400mm/5.0-6.3 IS

Vast Range


At first glance, the 100-400mm focal range does not look quite as impressive. In comparison, for example, this is a popular zoom with Canon users. But in the world of Micro Four Thirds systems, this lens covers twice the angle of view, ie. 200-800 mm. Comparatively, the search for a lens with a similar range without converters would be futile. The closest would probably be a hefty Sigma 300-800mm/ 5.6 weighing a whopping 6kg. The images below show the difference at both the minimum and maximum focal lengths.

If you are shooting at a 400mm focal length (equiv. to 800mm), you can quite easily ‘lose yourself’ when searching for an object at first, as it takes some practice to quickly find an animal in the viewfinder. It’s even more fun when you shoot hands-free from the ground using the flip-out monitor. You will appreciate this once you start enjoying another feature of this lens – a minimum focusing distance of 1.3m, as you will have the opportunity to take photos of other smaller insects than just dragonflies or butterflies. For example, focusing at 400mm (eq. 800mm) you can ‘macro’ magnify by 0.29x (eq. 0.57x), which is quite helpful. In comparison, for example, the 300mm/ 4 has a magnification of 0.24x. The only drawback is that it may take a while for you to find the wanted butterfly in your viewfinder.

Azure Bluet, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 400mm, ISO 500, f/6.3, 1/400s, handheld

Aperture of F/6.3


In addition to the many great principal specs, there is one that will probably be addressed by a lot of people, and that is its minimum aperture. Focusing at 300mm and 400mm, the minimum aperture is F/6.3. This is, of course, understandable with such compact lens dimensions, however, in practice, it will naturally affect the background blur, shutter speed and sharpness. A good rule of thumb to keep in mind is that the farther the background from the object, the more blurry it will be creating a pleasing bokeh. In some habitats, such as meadows, ponds, wetlands or fields, this won’t be a problem. Similarly, shooting certain stationary forest motifs such as orchids or owls etc, won’t pose any obstacles especially in combination with a tripod. However, if your main goal is to photograph for example fighting mouflons in the woods after sunset, this lens is not your ideal buddy. Essentially, you will have to raise your ISO, which in turn will undoubtedly affect all the fine details, luminance noise of your photo and any obstructions will push the ISO even higher. If on the other hand, your main aim is to photograph in the Zoo or take photos of ducks, herons, mudflies, butterflies, dragonflies, flowers and who knows what else, then I believe this lens can be your best mate.

Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS – handheld lens size

Fine Detail & Sharpness


Before I get into more detail about … well, fine details, I’d like first to mention a few points about the nomenclature. When chatting to my photographer colleagues about their lens capturing sharp, detailed photos, I often come across two statements. Colloquially speaking, they are expressed as “it’s clear as mud” or “it’s razor-sharp“. I’d like to expand this range a little, and similarly expressively, I’d describe it as follows: “clear as mud” – “meh” – “so-so” – “just peachy” – “razor-sharp“. Personally, I think that the amount of sharp in-focus details M.Zuiko 100-400mm captures is very good for its class, range and price. You are sometimes tempted to expect more, because looking at the photos themselves they are surprisingly very sharp and clear. But when you compare it with a photo taken for example with the aforementioned Olympus 300mm/ 4 IS, you can find that there can be even more sharpness and fine detail captured. This is perhaps due to the absence of a micro-detail the latter is blessed with. Anyone who’d expect that for half the price the amount of fine detail of this lens would be the same as with a prime 300mm lens will be disappointed due to unrealistic expectations. Nevertheless, this lens gets pretty close. But as I said, in my opinion, the sharpness scale has many more variables than simple ‘mud’ or ‘razor-sharp’, and I really think that the 100-400mm doesn’t have to be ashamed of its performance at all.

Red-tailed Laughingthrush, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 100mm, ISO 1600, f/5, 1/13s, handheld

How does M.Zuiko 100-400mm/ 5.0-6.3 IS compare with Panasonic 100-400mm/ 4.5-6.3 IOS (testing conditions)


When I had the lens on loan from Olympus, after a while I felt the need to try it side by side with the Panasonic 100-400 lens, which has been on the market for some time. In the end, it worked out thanks to the generosity of FotoŠkoda that kindly loaned it to me for a few days resulting in the amazing opportunity to try out both, the Olympus 100-400mm/ 5.0-6.3 IS and the side by side. At that moment, I got into a testing vortex as you can imagine the countless combinations of focal lengths and apertures. Field tests of wildlife are quite difficult because God knows why wild animals keep doing their own thing and leave whenever they want. After several target tests from my room window, I ended up going to the Prague Zoo for a day. It was very cloudy and it rained most of the day. I couldn’t have asked for better conditions for the test. The better the weather, the better the results, so it was also a stress test. Before this occasion, I knew the Panasonic zoom only from a handful of pictures and word of mouth from a few fellow photographers, who usually rated its longer end (400mm) as “clear as mud“. As you know, my scale is a little finer and I wouldn’t rate the Panasonic lens as harshly. As a matter of fact, I think it’s a long way from the “mud” and would rate its performance somewhere between so-so and just peachy. I parked my gear for a few hours at the pelican enclosure, where there is also always plenty of standing and flying wild herons. Unfortunately, the enclosure is not built with photographers in mind, so the surrounding vegetation is usually too close to the birds, hindering any creative process of an interesting photo making. Fortunately, due to rain, the birds barely moved and stood like statues. This gave me plenty of time to switch lenses between shots and add converters to a fixed 200mm. I photographed exclusively on the lowest available aperture value because, in my opinion, the comparison of sharpness is the most important. You can’t see much at F/8. Even so, when shooting from my hand under this cloudy sky and rainy weather the values I reached of 1/60s were fairly critical. In some photos, you may also notice that despite all my efforts, I did not manage to create a completely identical image (animals are simply monsters). During my visit to the Zoo, I also strolled through other enclosures taking several hundred photos, and I think I have quite a good idea of how the lenses compare.

Prague Zoo Pelican enclosure with two herons to compare sharpness and fine detail captured by the lenses.

Example of sharpness/ fine detail of both 400mm lenses at open aperture

Comparison of M.Zuiko 100-400mm/ 5.0-6.3 IS vs Panasonic 100-400mm/ 4.5-6.3 IOS (personal observations)


If you shoot at a focal length of around 200mm, both lenses perform very well. Similarly, at focal lengths of 300mm and 400mm, the results were also quite comparable, yet I found some differences in the presentation of the fine detail. Sometimes, I preferred Panasonic, other times Olympus, but on Panasonic, I almost always noticed a rather unflattering rendering of just out-of-focus areas, which emotionally diminished the perception of the optical clarity and precision as a whole. While the Olympus lens delivered only a little less fine details, Panasonic often produced slight flare up and colour fringing around edges associated with chromatic aberration. This is easier to show you in some examples at the link below. Based on this, I feel that the Olympus lens delivers slightly sharper more detailed images. As for control, I found Olympus much more comfortable to use, as, despite its larger dimensions, its design allows for a perfectly smooth operation of both rotating rings. The Panasonic lens, however, somewhat skipped a few times on the zoom ring and I needed about three attempts to hit exactly 200mm. It’s possible I’d break it in overtime, but at times it was very irritating especially when I wanted to compare the focal lengths but the heron would sadly decide to leave in the meantime.

Not every 400mm is a 400mm


When I target-tested the lenses at home on my models of lizards I also noticed something very interesting. I knew beforehand that zoom lenses are in fact shorter than the prime lenses of the same single focal length. But what surprised me was the difference between the two zooms. If you compared the size of the photographed object to a focal length of 400 mm with the mentioned lenses, then each is different from the same distance. With the Panasonic 100-400, the object is smaller and corresponds roughly to what the 342mm focal length looks like on the Olympus 100-400. The largest is an object on a prime Panasonic 200mm with 2x converter. What is (for me) no less interesting is that the greater the distance the fewer differences, respectively. This can be seen in the test photos in the next section below. From a practical point of view, this can be applied for macro photography, where the object will be larger when photographed by the Olympus lens at the same distance.



+ Workmanship – Olympus has (in my opinion) more precise manufacturing, although the feeling is more ‘plasticky’. Panasonic seems more spartan and rigid (a matter of personal taste).

+ Tactile Separation of Zoom and MF rings – Tactile separation of Focus and Zoom rings on Olympus is just excellent. When you hold the camera to your eye you know exactly which ring you rotate on the barrel. Panasonic has three equally grooved rings in a row and it’s easy sometimes to grab the Zoom ring instead of Focusing one.

+ Zoom Precision – Olympus has a much smoother and more precise zoom performance. When twisting the zoom with two fingers on the Panasonic, the values skip over the entire range.

+ MF Precision – Olympus has a perfectly fine & precise Focusing ring. Panasonic puts significantly more resistance.

+ Zoom Extension – Olympus extends less, holds the centre of gravity better.

+ Tripod Mount Rotation – Olympus can rotate its tripod mount 360°, Panasonic only 90° and only to one side. It cannot be positioned so that the shutter is down.

+ Tripod Mounting Plate – Olympus has a built-in rounded ArcaSwiss plate. It secures the lens better than a Panasonic square plate.

+ Lens AF Limiters – Olympus has three limiter settings on the lens, Panasonic has 2.

+ IS Sound Reduction When Shaking – Olympus has a much better built-in front IS, makes almost no sound when shaken. Panasonic rattles as if a faulty lens is loose inside.

+ Teleconverter – Olympus is compatible with TC 1.4x and TC 2x. Panasonic does not allow you to connect any TCs at all.

+ Zoom – Olympus zooms 400mm closer than Panasonic. 400mm on the Panasonic corresponds to about 342mm on the Olympus (at a distance of about 2m); at a greater distance, the difference disappears, though.

+ Full Functionality with Oly Body – Olympus allows you to use all the features, Panasonic does not allow ProCapture L (ProCapture H only) and composite macro.




+ Overall length – Panasonic is shorter (172mm vs. 206mm).

+ Total weight – Panasonic is lighter (985g vs. 1120g).

+ F/4 a 100mm – Panasonic has f/4 instead of Oly f/5 at the 100mm end

+ Tripod Mount Plate Removal – Panasonic can unscrew the plate altogether, it can be swapped around with Panasonic 200mm (one plate is sufficient for both). Olympus allows you to remove the entire mount after disconnecting the lens from the camera body.

+ More Detailed On-lens Length Inscription – Panasonic has more detailed zoom positions indicated on the lens – 100 – 150 – 200 -250 – 300 – 350 – 400 (Olympus – 100 – 150 – 200 – 300 – 400).

+ Zoom Lock – Panasonic can be locked in at any focal length, however, the lock is not fixed and the zoom can, with some difficulty, be moved further. Olympus can be locked only at 100mm.

Secretarybird, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 314mm, ISO 250, f/7.1, 1/320s, handheld

A picture is worth a thousand words


So that you can draw your own picture of the optical performance of Olympus’ new zoom, have a look at the link below to my Google Drive folder with a few sample photos. The first folder compares the fine details of both zooms. The second one contains 27 photos from the Olympus 100-400mm lens in full resolution. The file names can tell you the focal length used. It’s no spectacle in terms of the content, but I think it demonstrates well all we’ve discussed here. You will find there my direct JPG export of RAW files that I don’t usually distribute, which I believe will give you all the answers to your questions regarding sharpness and fine details. Apart from some minor cropping, all photos are unedited with full EXIF data. I used Capture One software to convert them in maximum quality. This will allow you to compare the photos from the two lenses in many different ways.




Disclaimer: Photographs are for your personal use ONLY. By opening the link, you agree that you will use the photos solely for your personal use and that you will not distribute or otherwise use them without the author’s permission.

Broad-bodied Chaser, Olympus E-M1 III, M.Zuiko 100-400mm/5.0-6.3 IS, 400mm, ISO 400, f/6.3, 1/400s, handheld

In conclusion


Olympus M.Zuiko 100-400mm/ 5.0-6.3 IS will surely please those who are looking for an economically appealing telephoto solution with a wide focal range taking full advantage of all the possibilities the focal length of 200-800mm in conjunction with a short focusing distance of 1.3m offers. It is especially interesting thanks to its compact & lightweight dimensions of about 1.2 kg allowing you to make handheld photographs of a variety of motifs. It is particularly well suited for wide, open habitats where the minimum aperture of F/6.3 works really well. Shooting in short series and choosing the sharpest one of the lot worked well for me. If your photos require the same focal range but a higher standard of output quality, it might be worth waiting until the end of 2020, when a second zoom M.Zuiko 150-400mm/ 4.5 IS lens with a built-in 1.25x converter was announced to arrive on the market. But it will be quite a different story.

<<< Check the review of my friend Rostislav Stach too [CZ only but worth a visit] >>>




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    Excellent photos !

  • Antonio

    Olympus does a good job with the lenses and an excellent job with the SW.
    Try looking at images taken with the Olympus lens by disabling lens corrections and you will find out how many flaws they have, including barrel distortion which once corrected makes the image appear larger.
    I speak as an Olympus user.

  • Edward Anderson

    Hi Petr,

    I am wondering if you noticed any loss of image quality on the Panasonic due to it being used on an Olympus body. I have a Panasonic 100-400 and plan to use it on an Olympus OM-D E-M1 ii body. Seeing that the 2 image stabilization systems do not work together, which should I have on? The lens or the camera or should I have both on?

    Thank you in advance for your reply and the excellent article above!

  • Gregory

    Petr: Very well done comparison. I have played with a couple of images taken with the 100-400mm Olympus to see if I could improve the sharpness of the images using Topaz DeNoise AI. I am happy to say that the Topaz DeNoise AI did a very good job of improving the sharpness of the images to the point, I would not hesitate to purchase this lens now. But I am waiting on the 150-400 1.25 to see where it will be in both price and image quality. Both I expect will be high!

  • Thomas Stirr

    Hi Petr,

    I really appreciate this hands-on review and your sample images. To me, seeing the work of a professional photographer and reading a real world assessment is worth far more than the typical recital of specifications and images of test patterns. I have my M.Zuiko 100-400 IS f/5-6.3 on order.


  • Bryan

    Damn those shots are fantastic saving for this lens and I don’t know how to get it here in the Philippines.

  • Herb408

    I’ve preordered this lens.
    I also tried the Panasonic version but both copies had too many problems so I gave up.

  • Stewart Baird

    Fantastic real world tests. I have the 300mm f4 and the Panasonic 200mm f2.8. I much prefer the feel of the Olympus in the hand (the 2.8 is really handy for sports under lights). I think the “in the hand” tests are true for most of this gear. You can’t just compare specs!

  • walter warburton

    Good review Petr, I use the Panasonic on a MK3body for wildlife pics, this set up works well for me.I dont think there is enough improvement to swap for the Oly lens, so I will wait for the 150-400test and price.

  • Robert Gonzales

    Thank you for the great comparation review. It is very helpful. I bought the Pana 100-400 a few years ago to match with a Oly E1 mk ii for a trip to Botswana. I also found the firmness in the zoom action to be annoying. However, I was happy with the zoom range and the sharpness for that trip. I also found that the in-lens stabilization for my lens copy worked better than the Oly in-body stabilization. Of course, they wouldn’t work together. Unfortunately, I had to send it twice to Pana for repair of auto-focus. After waiting forever for repair, I sold it. I was done. I felt I couldn’t depend on it. But I did miss the zoom range. So I am really glad to see this new Oly lens. I just don’t think I will be able to justify the cost of the upcoming 150-400.

  • Jon Culver

    Thanks Petr, very useful review! I bought the Pana 100-400 in 2016 and used it for three years. I experienced some of the same issues you mentioned with that lens and so in 2018 bought the Oly 300 f4 with TC14 and was delighted with the obvious upgrade in quality, brightness and image detail.

  • Adrian Harris

    Thank you for the detailed review Petr and congratulations on your beautiful image galleries.

  • Suseel Kamaraju

    Excellent review. I still don’t understand why Olympus lens which has slower aperture, non-metal build is still longer and heavier than Panasonic!

    • Petr Bambousek

      Hard to say. In similar way I don’t understand why Panasonic lock rotation of its tripod mount. One of the most suprising moment during my testing 😀 I am sure there will be some technical reason in both cases 🙂

      • Brad

        I too have received the same “surprise” with the tripod foot rotating unexpectedly 🙂
        The Prague zoo is such a treasure – i got to visit last year / ran the Prague marathon.
        Nice work — appreciate the honesty

  • Ian Barstow

    Brilliant review thank you, I am just downloading the images now but I have pre-ordered the lens this morning. I don’t think the 150-400 pro lens will be in my price range and this should work well for wildlife, Motorsport and moon images. I tried with the Pano 100-400 but just could not get on with it so been waiting for a lens like this for a while.
    I will be interested to see what the images are like when using the 2x converter with this lens.

  • Martin Gallego

    Excellent test, congratulations. I loved the comparison with the Panaleica! A virtual hug!


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