I own both. Since I got the 50-200 I've not used the 40-150. The 50-200 is superior in every respect (which given its cost is to be expected). The 40-150 is not a bad lens but it doesn't have the reach I need for photographing Badgers. And the 50-200 takes teleconverters very well. At last year's Fallow deer rutt I took some of the images with the MC14 attached then as the light improved switched to the MC20 (so that I could position myself a bit further away from the deer). You'd have to stare very hard at the screen at 100% magnification to see the very slight difference is sharpness. At anything other than pixel peeping you can't see any difference.

As to size and weight, yes the 50-200 is obviously larger than the 40-150 and is slightly heavier but the weight difference is trivial. I can get my 300/f4, 50-200, two bodies, both teleconverters and either a standard zoom or the 60mm macro into my 20 litre backpack and still have room for some snacks. This gives me a very portable kit weighing about 7.5 KG which is capable of handling just about any wildlife photography scenario (apart from underwater obviously).

You can get a used copy of the 40-150 and the 300mm F4 for less than what you pay for the 50-200mm. Even used.

The 50-200 is just too big for me, but I'm sure it's a great lens. Nice comparison, thanks for sharing.

Loved the video but youtube skipped that final part about cost for some reason...

I think this is really a testament to how well the glass in that 40-150 is that it can even stand up to the 50-200 in terms of IQ, but I'm automatically going for that if I go to OM Systems. I'm not a politician and can't funnel that kind of coin my way yet but that's definitely the lens for me.

It’s like comparing tv screens side by side when you’re in store.  You’re sure to see some minor differences but in isolation you would never know so minor are those differences.  The 50-200 is the better lens but….unless you really have the need for that reach and stabilisation then go for it.  As the owner of the 40-150 it does what I need even with the TC on it.  Not a lens that comes out often as I generally like to travel light but I am blown away with the quality out of it when I use it…and I purchased it new at less than a third the current price of the 50-200 with the 1.4x tc.  What’s not to like?…and it’s smaller!

I'm a serious amateur.  75% of my photos are wildlife.  Between my 40-150 f2.8 and my 150-400 big white, and mc14 tc, I have everything I need.  I just returned from Yellowstone and Teton and I had both these lenses on my two OM1 mk 1 bodies and that had everything covered.  Except for an occasional landscape and I have 12-40 f2.8 and 8-18 Leica for that.

We can only shoot one lens at a time in real life. I wanted to downsize and simplify my nature photography. For my experience with all of these OM pro lenses, the one I will miss the least 'great moments' from my point of view is the 50-200/2.8. I've been shooting professionally and personally for several decades back well into film era. For me, selling the 40-150/2.8, 100-400/mkII, and 300/4 makes sense from a use standpoint. With the trajectory of software and my own abilities to get very close to subjects, and preference for more environmental photographs, it was an easy choice. My indoor event work is handled by my Sony A1 and fast zooms. My macro and astro work, aside from dedicated gear, is handled by OM and primes/macro lenses. Ideally, with today's superb glass, sensor dynamic range, and optimized software, I can often get by with a single setup compared to past years carrying multiple cameras at a time.

The solution is simple, have both. I think I will stilll travel overseas with the 40-150 due to size as I have found it to be a wonderful travel lens.

I just switched from FF Pentax to the OM1 MK2 and the 50-200 and f4 8-25 for an upcoming trip to Europe. The main reason was to save weight when traveling. Then when packing I decide the 50-200 was to big for this trip and i got the 40-150. It was a great trip but i ended up using the 8-25 90 % of the time. Over all I love the OM SYSTEM equipment. Not rich but I am retired and have more money then time so I bought everything I wanted now.

Got it, will hold onto my kid for something even better!

Jokes aside, thanks for the concise and fair comparison! I think you are right, for most people (like me), the 40-150mm is still an incredible lens! But for those who need that extra reach/features for more critical uses (and has the budget), the 50-200mm is a no-brainer.

I'm a hobbyist wildlife photog and as much as I want the 50-200mm, I cannot justify the spend yet. But as someone who really values portability, I the 40-150mm + 1.4x telecon is such a good kit for me. Thanks again for the comparison and helping me keep my money (and child!).

The background bokeh is quite "nervous" on both of them.  I have the 40-150 and that is the only feature of the lens I don't like.  Ironically, foreground bokeh is softer - wish they had designed it the other way around...

The OM raws are so good looking out of camera it blew me away the first time. My Nikon and Sony raws looked yucky but I’ve pushed out unedited OM raw files to JPEG with essentially zero edits

I just got the 40-150 from the OM reconditioned eBay store for $1,175 shipped (would've been $1,300 but got a small refund due to them not shipping it with a case mentioned in the listing.) Bought it during one of their 20% off sales. Spoke to one of their reps at a camera store recently and he said almost everything in there didn't even need to be fixed and is just Amazon returns that they can no longer sell as "new", but it basically is.

For me, getting this lens for a third of the cost of the 50-200 was a no-brainer, though I'm sure everything you're saying about the 50-200 is true. I'm saving up for the 150-400 and it will be my main lens once I have it (currently using a Canon R7 w/ 200-800 for super-tele.) I couldn't justify the 50-200 when it would never be my main go-to lens. Even if I go on a trip someday where the main wildlife subjects will be larger, close animals; I'm sure the 40-150 will perform fantastic. I enjoy its smaller size and the collapsable lens hood is awesome. Most importantly, I'm thrilled with the IQ.

I have used my 40-150 since I got the 50-200.

I carry my om-1 with 40-150mm f2.8 in my jacket pocket in colder times 😅 I can even get the 300mm f4 in the pocket, but more struggle to get it out 😅 Columbia winter jacket and rain/wind blocker summer jacket.

In general, I agree with pretty much everything stated. I think the challenge I have found in the MFT community is there is a huge preference towards "good enough" and it has to fit in my back pocket and I want it cheap. I photograph wildlife and was shooting the top tier lenses from Nikon. Top tier primes that most, even in FF land, won't invest in. Lenses that almost create light. While there is a lot of cool wildlife near me (I was shooting macro images of a mom Wolf spider with babies on her back from in our front yard today) and within driving distance. But, a few years back the size and weight of the gear was getting to be an issue - in terms of limitations from airlines. When I heard of MFT, I was pretty skeptical - but I'm a scientist in training and at heart - so test - evaluate the kinds of images that are important to me. The MFT gear, which meant the 40-150 mentioned here and the 300mm f/4 could match what I was getting from the FF gear . . . in daylight and lowlight action. Fast forward . . .

While the 40-150 is an excellent lens, the 50-200 is the better lens. When you come from FF land - this MFT gear is comparatively cheap for the quality of the gear and results you can get if shot well. Now my go to kit is the 12-40 f/2.8, the 50-200 f/2.8, and big white. I would submit there is no zoom lens in FF land that is better than the 50-200. I would not say that about the 40-150. While the 40-150 is an excellent lens, the Nikon 70-200 f/2.8 is better - a bit sharper and much better bokeh. If you are mindful of what you are doing, you can get closer in both departments with the 40-150, but it's easier with the 50-200, and that added range IS a big deal.

Something that seems lost on the MFT community: The larger lens diameter on the 50-200 allows it to capture much more light than the 40-150. That is a big deal that shouldn't be overlooked, nor taken for granted. It is a practical reason the price is higher - bigger pieces of high quality glass and likely built to a higher standard will always add to the price of a lens. And, just because the 50-200 is, IMO, the better of the two - it doesn't make the 40-150 a bad lens. If that focal range works for you, without needing the TC all the time, then learn to shoot it to it's best ability and you're all good. I aim to shoot as much as possible without added glass - it can lower IQ, lower light, and make bokeh busier - that is for me.

At the end of the day, if you are happy with the results you are getting with the gear you have, then you have what is right for you. At different parts of my skill journey, I was finding that the quality limitations in my work, were lenses. When I took the next step up the lens quality ladder, I then had to develop the skill to get the best from that. This was all before I came to MFT land. That said, I know from the years of teaching photography classes and guiding local trips, I know that most doing photography as a hobby do not have that same drive for quality, as I do - nor need to. But, when OM systems have been putting out such better pro-grade gear, I really appreciate it - and when I am on trips with others, often shooting APC or FF, they are jealous of my results - and in a case or two, have switched after the trip. MFT really can produce top tier results and I think the 50-200 is a real asset.

What if my child never cleans up after himself? Do I then sell him and get the 50-200? 😂

The one thing that would convince me to get the 50-200 is if I wanted to lighten my camera bag. On the other hand, I already have the 40-150, 300 f4, and PL 200 2.8 paid for. The 50-200 is still a hell of a proposition.

For weddings I think I rather have the 40-150mm f2.8 just because its smaller. But I use the Panasonic 35-100mm f2.8 because that is even smaller. My camera backpacks are packed I don't think I could even get a 40-150mm f2.8 in my backpack. LOL. I bring two backpacks to weddings.

Even With YouTube's Compression... I See A Bit More Saturation In The Colors With The 50-200 Which I Like.  Could Be More Dynamic Range Maybe?  📷📷📷