The Sweet Spot

RLight wrote:

Alastair Norcross wrote:

Here are some that show what I'm getting at:

Can you do these on the R with 28-70 F2 or 24-70 F2.8? Yes. Better results? No. Bigger, heavier, (much) more expensive? Definitely.

Once you lose the fixation with the shallowest possible depth of field, and consider what actually makes for good portraits of various kinds, you realize that the M6II, with available lenses (EF-M mount), can do pretty much all that the R can do. Are there some situations where the R and full frame lenses can get you better results, even if only marginally? Yes, of course (though your examples weren't of those situations). Is the slight improvement for those few possible situations worth the extra expense and weight and size of the full frame combination? That's a question for each of us, in consultation with our financial advisors and personal trainers. Is it worth a difference in score on a review? That depends on whether the scoring is relative to other cameras in the same class, or to all cameras available. If the former, no. There are no other APS-C cameras that do better than the M6II. The latest Sony and Fuji APS-C will do as well, especially with the same lenses (for Sony) or similar (for Fuji), but not any better. And no, the difference between 1.5 and 1.6 crop is not relevant here. It's utterly trivial. If we're scoring relative to all cameras, perhaps the R is worth 5/5 and the M6II is worth 4.5/5. But even that difference is too large, for the tiny number of possible situations where you'll actually appreciate the difference in results.

Nice shots, and we're on the same page; how much of a difference does it make?

Where we are on a different page is I'm arguing those shots, could've been taken on a Fuji X-T30 with 56mm f/1.2, or A6400 and the same lens for the E mount, and you don't have to worry about backing up, and it would be a more natural framing, and, you'd have access to a f/2.8 native zoom. These are excellent examples, and demonstrate the Sigma 56's IQ well, but, what you don't see are the images you couldn't get. That's something that doesn't show up unless I show you an image I got from something that could've which I did.

The difference between Sony crop and Canon crop is utterly meaningless and nowhere near the difference you are making it out to be.  The actual crop factors are 1.53 and 1.61 respectively.  Here is one of the images from above that highlights the difference in framing that you would see if you were using the Sigma 56mm f/1.4 on Sony vs Canon

The VERY tiny difference in framing with the same lens on Sony vs Canon crop camera

The difference in framing on the two systems is equivalent to cropping an image from the M6 II from 6960x4640 down to 6612x4408.  Again, utterly meaningless.