Hi John, no disagreement from me there. I was just talking about the low extended range characteristics previously.
As for pushing in post, we’re not at an ISO invariant sensor yet. Just approaching it.
If we did have truly zero read noise, the only noise we’d see in an image is shot noise which is inheritantly there and part of the nature of light. So digital scaling would truly be the best solution because you would scale to the correct brightness using a curve and be able to preserve every bit of highlight captured at the base ISO rather than clip a stop of highlight every full iso stop you go up.
Actually even today with some of the best sensors, provided you don’t push too crazily, if you have a high DR scene pushing in post may get you a higher DR final output albeit a bit noisier too.

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Hi Poider, sorry for going a bit off course.
As for m43, I did a review of the original EM-5, published here on Ausphotography. Have a search for it if you’re interested. It was a long time ago but it was still largely a great experience for me. I keep a constant lookout for if there is a good op to rejoin m43.
I still think the 75/1.8 is one of the best lenses I’ve used in any format.
And I think the dual IS on the newest models are largely unmatched in other formats too.
With the right lenses, I’m confident m43 should comfortably meet your bar of quality acceptance.