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thxbb12 · 03-08-2018, 09:13 PM

Very informative read!

https://www.lensrentals.com/blog/2018/03...-fabulous/

Sammy · 03-09-2018, 07:37 AM

Yes, very interesting indeed. Once again sample variation is very important. A good sample of the Pana "Noctitron" beats them all, but unfortunately it seems that only 1 out 3 samples is that good.

**Klaus** · 03-09-2018, 11:01 AM

(03-09-2018, 07:37 AM)Sammy Wrote: Yes, very interesting indeed. Once again sample variation is very important. A good sample of the Pana "Noctitron" beats them all, but unfortunately it seems that only 1 out 3 samples is that good.

Yeah, the Pana QC is ...

JJ_SO · 03-09-2018, 11:16 AM

I found the field curvature pretty impressive. In DSLR land that would be a serious problem, but mirrorless bodies don't care much about as long as Eye detection is working well.

Brightcolours · 03-09-2018, 11:44 AM

Huh? It makes no difference whether the camera body has a mirror or not, the field curvature in the image will be exactly the same. Field curvature does not impact AF either.

JJ_SO · 03-09-2018, 12:25 PM

(03-09-2018, 11:44 AM)Brightcolours Wrote: Huh? It makes no difference whether the camera body has a mirror or not, the field curvature in the image will be exactly the same. Field curvature does not impact AF either.

Sure, but in a DSLR it's a limited area of AF points - and at worst, there's also a different pane of focus unit to sensor. No matter how you try to adjust AF, it's always an indirect system and only at best and lowest tolerances, the outer AF points will have the same micro-adjustment values.

But if the adjustment values are different - and I made a a couple of tests with FoCal, so I know how big the differences are - the system will not deliver maximum sharpness. Which is needed at wide open lenses.

I know you're thinking the system usually is perfect if the assembly was done as careful as one could expect. However, if there are sample variations of lenses, I cannot deny there will also be sample variation in camera bodies. And all I'm saying is, it doesn't matter too much for mirrorless systems.

Rover · 03-09-2018, 12:25 PM

That was enlightening to read.

Brightcolours · 03-09-2018, 01:55 PM

Stil makes no sense, field curvature does not look at on how a camera is constructed. The projected image will always be the same with the same field curvature issues.

borisbg · 03-09-2018, 07:33 PM

JoJo is talking about how focus curvature affects AF not the final image. If one focuses in life view then the field between camera types is leveled.

**Klaus** · 03-09-2018, 09:46 PM

I think field curvature is a bit overblown there. FC is usually an issue in very shallow DoF - and that Oly lens is a 90mm f/3.6 to start with ...