Retesting Olympus M.Zuiko 100-400mm F5-6.3 IS Lens In Better Light

I loaned the Olympus M.Zuiko 100-400mm F5-6.3 IS lens from OMD World Imaging (sole distributor for Olympus products in Malaysia) to revisit the lens performance, this time in better lighting conditions. I have done a full review for Olympus 100-400mm lens before (click here) but the sample shots were taken in cloudy weather, and high ISO numbers. I thought that did not do justice to show off what the lens is truly capable of, so this time, I was determined to shoot with only low ISO and in ideal lighting to see just how sharp this Olympus 100-400mm can be! And boy oh boy, spoilers alert - the lens is incredibly sharp.

I have made a video for this same topic, so if you prefer to watch, go to my YouTube here (click). 

Lens and OM-D body combination is still perfectly hand-holdable, and handling was quite good. Lens feels balanced, I had no issue using this combination for about 3 hours shooting duration non-stop. 

I am an Olympus Visionary, an ambassador to the Olympus brand. The 100-400mm lens was not mine and was on loan from OMD World Imaging, and I have returned the lens. This is not a full review, and I have mentioned, I did the review before. 

To be fair, I thought my first review was more representative of real world shooting conditions - birds and wildlife they don't just stand out in the open, broad sunlight posing for you readily to shoot. Most of the times, they would hide in worst places, in heavy shade, under a tree, in the bush, away from direct sunlight, and you just have to deal with low light. In such scenarios, having not that wide open aperture of F5-6.3, when you zoom in to the full telephoto end (which you want to do, when you buy this lens), at F6.3, you don't have a lot of light to work with, and you have no choice but to push the ISO numbers higher. I used ISO800 to 1000 for quite a few shots, and this degraded the image quality, images appear softer, not as sharp as they could have been if I lowered the ISO numbers, and they look flatter with less contrast. I'd like to argue that my first review, though shot with higher ISO numbers in less than ideal light, was a more accurate review showing how the Olympus 100-400mm lens handles in difficult situations. 

I hear some comments saying that the lens could have been better if I did not shoot in low light. That is also true. So for this particular session, I went to the Kuala Lumpur Bird Park again, and thankfully the weather was cooperating this time (if you have seen some of my recent videos of me being trapped in thunderstorms). 

Here is the list of my shooting setup, for those who are interested about technical details.
Camera: Olympus OM-D E-M1 Mark III
No Tripod used, all shots taken hand-held
Aperture Priority mode used
ISO200 for most shots, and restricted to 400 (though I did go to 500 for some shots unintentionally)
S-AF mode, I moved the focusing area manually for each shot. 
All images shot in RAW and post processed in Capture One Pro. 
Minimal tweaks in editing, only contrast, exposure and a bit of white balance. I left the sharpening and noise reduction settings to default. 
And I only chose birds in good light, or at least I can manage within the limitations of shooting with low ISO. 

The results? Nothing short of impressive. 



Crop from previous image



Crop from previous image



Under abundant sun light, the lens truly shines. The Olympus 100-400mm lens is super sharp, and the sharpness is very consistent throughout the entire zoom range, having only minor dip in sharpness at the very long end of 400mm. The lens can resolve insane amount of fine details, the per pixel sharpness is very good, and I'd say almost as good as a PRO lens. In fact, if you show me images shot with this lens in good light, without telling me you took them with this lens, I'd think you have used a PRO lens (40-150mm PRO, or 300mm PRO). Though I  must admit, if there is a side by side comparison, I'd still be able to see the minor difference, and the PRO lenses still have the advantage in optical superiority. The Olympus 100-400mm lens, being a non-Pro lens, can deliver crazy sharp images, with excellent contrast, rendering images that look ultra-realistic and true to life. 

I did notice slight drop in sharpness when you zoom past 300mm, and especially at the furthest end of 400mm, but to be entirely honest, even at 400mm, the lens is still nothing short of spectacular. The sharpness is more than good enough and I'd not hesitate to use it, and if you are purchasing this lens, be confident to know that at 400mm end, you'd still get fantastic results. I have plenty of crops at 400mm end to prove how amazing this lens is, and you should not worry too much. The only challenge is to get enough light to work with, because things can drastically change when you shoot up the ISO to 1000, or beyond. It is not the noise that is the problem here, but loss of pixel integrity and general contrast, you get images with less pop, and they look flatter in general. 

The bokeh is very smooth and pleasing. I like how the subjects gradually transitions to the out of focus area, there is no sharp, sudden cut outs, and the bokeh quality is very good for a non-PRO lens. In fact, I'd argue that the bokeh looks better than some of the older PRO lenses from Olympus. The buttery smooth rendering helps in adding depth to the images, as the lens captures super sharp main subject in focus with plenty of details and contrast, the background that is creamy and smooth helped boosted the illusion of 3D effect. 

I had Fried Chicken for lunch after this shooting session


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Crop from previous image




I know Olympus has just launched the much anticipated M.Zuiko 150-400mm F4 IS PRO earlier this year, and that is a superior lens in every regard. I have no had a chance to try the lens yet, there is no sample unit available in Malaysia, and let's be entirely honest here, I am nowhere near capable to afford that lens, or justifying spending my hard-earn cash for the lens I don't really need. Not having seen the lens in person, or tested it extensively, I am in no position to comment about the 150-400mm PRO, or give recommendations. 

I guess, if you are a professional photographer earning from wildlife photography, you shoot birds, or sports and you need that super far reach, yet at the same time you want the best out of the best Micro Four Thirds system has to offer for a lens at that massive zoom range, you can't go wrong with the M.Zuiko 150-400mm PRO, it is after all, a PRO grade lens, with a massive price tag. Reviews have been overwhelmingly positive everywhere. On the other hand, if you are like me, who is not a wildlife photographer, who does not shoot birds often (testing the lens does not count) and is not a sports photographer by profession, if I still want that massive reach in case I need it, then the 100-400mm lens makes perfect sense, and the lens is within the affordable range for most people. 

The Olympus 100-400mm offers a lot for the price it asks for - some may complain it is on the higher side, but I get to differ. The 100-400mm has built in image stabilization, which is effective - look at all the shots I have shown here, some even taken at 1/20 seconds hand-held, and still came out super sharp! The lens also has incredibly fast and reliable Autofocus performance, and I did test the lens on E-M1 Mark III, the accuracy is consistent, I had extremely high hit rate. You get great build quality, the lens is made of part metal and part plastic, very well constructed I must say, you can feel it as you handle it with your hands. Furthermore, the 100-400mm lens is also fully weather-sealed, an important feature to have if you do a lot of outdoor photography, which I'd think you do if you are considering this lens. The list goes on - you can further extend the reach of this lens by adding teleconverters - MC20 or MC14, at the maximum range you can effectively double the reach to a whooping 800mm! That is a lot you are getting out of this one 100-400mm lens, and don't forget - I have also proven the optical design is very good, you get excellent image quality!











I do enjoy shooting with the Olympus M.Zuiko 100-400mm tremendously, and it is a great lens to have if you intend to dive into wildlife photography, or shooting birds outdoor, but you don't want to immediately sell off one kidney to fund for the 150-400mm PRO. You still get the same reach - which is the most important factor, and you get incredibly sharp images as well, and the one advantage not to be left out, the lens is small and light enough to be used hand-held. I am glad Olympus is exploring the longer end of lenses, I think this is where they truly shine!

I am sure by now. some of you have the Olympus 100-400mm lens already and have shot quite a bit with the lens, please share your thoughts and experience using the lens! Do you think the lens is sharp, and do you need to use higher ISO numbers often? I am curious to find out how others use the lens, or if you are lucky to get good light to work with all the time. I surely don't. 

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  1. Hey Robin, thanks for all your hard work in posting informative content around Olympus products. I recently moved from Canon over to omd E-M1 Mark iii and have the 100-400mm lens with the mc1.4 tele converter. I shoot wildlife in manual with auto ISO in low light conditions. The iso definitely bumps up higher than expected and topaz de-noise has become part of my workflow. The results are great and I can get very sharp images even at higher iso. It has been a positive move for me.

    Pre-covid I spent some time in KL and Borneo so it is like revisiting my holiday watching some of your feed!


    1. Thanks for the kind words, Paul. Indeed, in real life shooting the wildlife and birds normally hide in shaded area and we do need higher ISO numbers.

  2. Hi Robin,
    First I want to say that I love the new look of your blog! I clicked over for my usual Robin Wong fix and was blown away; I ran through all the header links and I think it's great, and I love the new "framed" presentation of each photo with its info.

    I really hope you won't mind if I point something out - the proper way is to say "I borrowed something," not "I loaned something." You use "loaned" only when you're the one giving the thing to someone else. English - go figure.

    Excellent bird photos and yet another article tempting me away from my 75-300 to that 100-400...sigh