Crop Factor, Low Light and Aperture with m4/3 lenses?

Started Jun 15, 2014 | Discussions thread
Just another Canon shooter
Just another Canon shooter Veteran Member • Posts: 4,691
Re: A picture is worth...

Anders W wrote:

Noise can't be "blurred". It's not affected by the optical resolution. The E-M1 shows less noise.

Of course it can, it is called NR,

NR blurs the detail. It reduces the noise.

It reduces the noise by blurring it. The noise in the deep blue has very non-Poisson structure, as simple as that.

which can be done after the demosaicing, or incorporated in the demoasicing algorithm. Shot noise is of Poisson type, even on a Bayer sensor. If we make it B&W for simplicity, it has a well defined structure and spectrum. Missing high frequencies with the low frequencies present is an evidence of blurring, or NR, or call it whatever you want.

So are you saying that ACR secretly applies more NR to the E-M1 than to the other cameras although the NR sliders are set 0 in all cases?

You cannot separate demosaicing from NR. The old ACR process, for example, has "hidden NR" in it, by your logic.

Go to ISO 100. The deep blue square has more blurred borders compared to the others. Look at the 6D crop - no such thing.

The borders are a matter of resolution. Note what I already said about the E-M1 shot not being appropriate for judging resolution.

Resolution magically changes from one color to another?

It does not need to do that in order to blur the border.

It blurs one border but not another, while the camera next to it does not do that.

Lens aberrations cannot change the structure of the noise of a uniform target.

Right. That's one thing I had in mind when I said noise can't be blurred.

But processing can.

 Just another Canon shooter's gear list:Just another Canon shooter's gear list
Canon EOS 5D Mark II Canon EF 15mm f/2.8 Fisheye Canon EF 35mm F1.4L USM Canon EF 50mm f/1.2L USM Canon EF 135mm F2L USM +4 more
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