@85mm wide-open from about 8' iso 200 M4/3 (harsh situation test, backlit, low sun, sky, leaves/twigs, aperture wide-open) If there is a weakness, wide-open at 85mm is it? Backward reviewing, the very best the worst can do. Not the best a lens can do, the best the worst portion of a lens, from its weakest position, can do and in unkind conditions as well. Being absorbed with best all the time is boring...what's the best of the worst part of a lens?
Some nice photos, and showing yet another reason not to bypass a lens for it's perceived issues that some lenses (sadly) get a bad rep for. I also think you're illustrating what might be part of a dying ritual of an older and a more methodical era, where one actually takes the time to test a lens under a variety of conditions, instead of assuming that "my well researched lens is perfectly capable of performing brilliantly under any and every circumstance".
You get a couple of added bonuses to using it on a M4/3 body too... cropping to the sweet spot, and a tighter field of view when capturing any 'unwilling to pose' fauna that are usually hard to get close to. When hunger takes over for the fear of people, it's gets easier, but it helps to tighten up for better details when you get the built-in byproduct of cropped sensors using full frame legacy glass.
...and? Reliable adapters, because the Fotoga 'c/y-M4/3' has its own issues above, yet my c/y to FX is perfect. I don't adapt lenses to my 6D, I know what to expect from them generally speaking in their close to normal 35mm film perspectives. I'm older than dirt to many people, so the one thing fresh for me is seeing what I had seen for years and years, in a whole new perspective? I always point out I use M4/3 on purpose, a 28-85 is closer to 56-170mm of course, sort of ..but at 56mm you have a wider perception with distortion and field curvature (where any fifty is typically well corrected and balanced ?). It's always bothered me that reviews/opinions shared are not categorized? Sure it's a specific lens, but the results are anything but specific depending on format...
This plants a seed, whenever I see something that can obviously skew things... one lens, 3 formats and each unique and providing different results. It opens the door to having opinions that are irrelevant to our own format of interest? Can't correct the way people are but we should correct how we categorize and be very specific; Film, Full Frame, Crop Sensor, M4/3?
tHE 28-85 is a great street lens on smaller sensors, it's one you can grab and quickly set, focus and zoom with confidence - I make mistakes and I goof, it isn't goof proof but knowing wide open performance is there and everything else that goes into handling and positioning... Second guessing and uncertainty are shot killers in Street Photography, confidence is key. Mine is an excellent copy, haze free and no coating issues...on MFT stopped down it may make a good hiking lens and I'll see what it does outdoors in nature? I had the Viv 28-90 Series 1 and 28-85 and have many images on file.
As far as adapters go, I've had my own issues with them and have relearned the same lesson over and over again - that acceptable quality should never be assumed, and it also isn't a regulated requirement where everyone will get XX amount of it with every purchase. I've pretty much limited the generic adapters I use, to K&F (Sony) and FotoDiox (Sony and M4/3). The main adapter I use is a Novoflex C/Y to E-Mount, and it was well worth the winning bid at auction to get one. The cheap Chinese adapter quality can spin on a dime to be wildly out of whack more often than you'd think should be possible.
You bring up the point about differences across formats, but most users might tend to forget that in the digital world, there's no such thing as a universal sensor. In the film side of adaption, everyone has an additional choice of what film stock to use. Not every roll of color negative is the same in color rendition and it's obvious that when swapped out with the same 'hardware', there will be a different result seen in the finished photo. The same applies to sensors, but many users assume (maybe it's because they're led to it by the maker) that sensors are neutral. They are tuned in somewhat the same way that film is.
It even happens when the underlying camera is rebranded. A Leitz V-Lux (any version) is a rebranded Panasonic Lumix, and other than logo changes on the outside and a substitution of glass - there's a reworked sensor to match Leica's preferences. It also happens when each maker designs and programs the purchased sensor's processor chips that they buy from a select few sensor makers. Sony sensors are in far more cameras than those branded under the Sony label, as not every camera maker makes their own sensors. Samsung and Toshiba have their sensors in multiple cameras, just like Sony does.
DxO started their company life as an engineering firm that helped camera makers with their digital 'tuning', and sometime later they started to produce their own digital darkroom software. As part of that software's functionality, I can in effect, retune my Sony Exmor sensors to render like I'd used a Hasselblad X1D or a Nikon Z6 body. The differences can sometimes be subtle, but obvious when you can quickly swap their digital profiles to view the results on-screen.
I agree, I understand.... "most users" can only operate on the information they posses or have. My point is, early on these differences were pointed out regularly and did not stick. The information did not stick because it was countered by the allowance of unregulated opinions based on a specific lens only with no efforts to correct a marketing scheme and left wide open as an ambiguous information reference to specific lenses in general. The trouble started when crop sensors were labeled with 35mm film perspective focal ranges for marketing purposes, the dumbest idea in the industry ever because it's illogical and regrettably, now ingrained. So the generalized casual user (whom ever that is?) was educated incorrectly with marketing gimmicks, I see 100 commercials by Pharma doing that daily and it's what industry does, throws things at consumers and hope they stick on a few? I have a Tokina 16-28 on my 6D and a 50 year old man comes up and ask, "how wide does that go?" I said, "16mm". He said, "is that all? Mine goes to 8mm". Millennial's I personally give credit to and the basis for my entire point. They tend to as a group, research things thoroughly. The information they are getting is corrupted because marketing instilled incorrect information in their minds hoping it would stick...and it did.
I hope when I'm gone, that cleaning up the misinformation is a goal of some generation who hopefully has only one political agenda, the Truth. Dreams are made to come true, or what's the use I say?
Dr. Lui of St. Louie compiled a list of old Photodo lens ratings complied over the years from Modern and Popular Photography test. It happens to lack Yashica lenses? The hard-drive which held the file sank to the bottom of despair. He's a math genius, the brains behind Moneyball and the A's and much more, besides being obsessed with Mathematics he was absorbed with Lenses. He has the best base list to this day regarding old glass, and people should often resort to it I say. It was the very first ever broad spectrum rating ever attempted and performed - and he's not capable of skewing anything because cheating is wholly illogical and the polar opposite of his intentions.
Who will the President Hate next, stay tuned to Fox News and be sure to see how we directed him to our next choice?