09-13-2015, 12:02 PM
I think DXO data is actually pretty useful, but the headline numbers aren't. The PMP figures are a great idea in principle, though I'd like a little more transparency about how they are calculated (i.e. what the weighting between apertures and locations in the image field is: I have heard from them that it is weighted towards the best aperture, and towards the centre of the field, but not by how much)
Anyhow back on topic: most of these differences are between the strengths of the AA filers on the various APSC cameras. If you look at the Nikon 16-35 on the D800 and compare on different APSC cameras, it varies by much more than the MP amount explains, and tracks how strong the AA filter is. Remember in the case of the A7r and the A6000 you are comparing an sensor with no AA to one with.
Anyhow back on topic: most of these differences are between the strengths of the AA filers on the various APSC cameras. If you look at the Nikon 16-35 on the D800 and compare on different APSC cameras, it varies by much more than the MP amount explains, and tracks how strong the AA filter is. Remember in the case of the A7r and the A6000 you are comparing an sensor with no AA to one with.