Re: M.Zuiko Digital ED 50-200mm f/2.8 IS PRO is coming!?
So I did that testing today...again, I cannot stress enough that my methods are perfect...but this is incredibly hard to do. Luckily it's very rainy/overcast today in the location of my home where I did this that allowed even lighting and I didn't have to set up some complicated lighting setup.
The test is to show what @ketang is mentioning about the field curvature at close distances wide open...so being level is not as important, but keeping the subject parallel to the sensor is important here but since we're not dealing with macro distances, there's some relatively forgiving tolerances.
the setup:
- camera on a heavy 5-series Gitzo tripod with geared column with Arca Swiss C1 head...stability of the tripod is never going to be in question
- I am using an el-cheapo DGK resolution chart but is good enough for this testing. The chart is attached to a McStand copy stand magnetic board standing upright. I should have made sure that the thing is level (using bubble level) but the results will show that (thankfully) it wasn't necessary.
- All used MF with focus-peaking.
- @ketangs concerns do have merit. You can see that the 50-200 at 2.8 does have some astigmatism on the upper right and left corners (it's not present in the middle top edge so it's not DoF issue)...but it's ever so slight that you have to go 300% to see it. I'm not bothered by it because i rarely find myself having the need for that use case, but it can be annoying for a lens at this price, even if it's a result of sample variation.
- the 40-150 is basically faultless, maybe a little bit of vignetting that can be easily corrected. it's the GOAT for a reason.
- the 150-400 has a very slight astigmatism (even less so than the 50-200) on the upper right corner...but yeah overall still very good.
To be clear, the conclusion here is not "my god these expensive lenses are trash." It's all relative, and all these lenses are very good...it's just that the 40-150 is THAT good. Peak Olympus (lol pun) right there.
Oct 13, 2025 at 01:31 PM
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