Hi,
I would say that DxO is a bit less than clear in describing the measurements they do.
Anyway, I would guess that the data they show is MTF at a given frequency.
Resolution is by definition the line pair per millimetres were MTF drops to a small value, like 9% or even lower values.
So I would say that resolution is mostly identical to the resolution of the sensor, while sharpness more depends on MTF, and actually more on MTF at lower frequencies than at high frequencies.
So, yes, the interpretation you make is reasonable, although I feel that resolution is a bit of a misnomer in the context.
These two papers by Dr. Hubert Nasse of Zeiss explain things pretty well:
http://www.zeiss.com/content/dam/Photography/new/pdf/en/cln_archiv/cln30_en_web_special_mtf_01.pdfhttp://www.zeiss.com/content/dam/Photography/new/pdf/en/cln_archiv/cln31_en_web_special_mtf_02.pdfOne thing to keep in mind is that human perception of sharpness is dominated by low to medium frequency detail. A better lens generally would transfer more contrast at low to medium frequencies than a lens of less image quality. But the real figure to check is MTF of lens * MTF of sensor and there is a lot more to image quality than just MTF.
Best regards
Erik
DxO has many measurements of lenses and cameras. There is the Mpix which is sort of described but it is not very clear what exactly it means except that a higher number probably means a better resolving lens on a given camera. The accutance profile seems like a god place to judge a lens and camera combination as you can for a zoom lens select the focal length and the aperture. What is not clear to me is how the accutance % relates to resolution. I have read the descriptions http://www.dxomark.com/About/In-depth-measurements/Measurements/Sharpness but still it does not me at least spell out what the curves really mean.
The attached comparison shows Canon 5D III and 5DsR on the Canon 24-70 f/2.8L II lens which is rated at 32 Mpix for the 5DsR and the Nikon 24-70 f/2.8G ED on the D810 rated at 21 Mpix. We can see that the 5DsR and D810 accutance % is the same in the center of the lens, but does that mean that the resolution is the same?
We can also see that the 5D III accutance % goes higher than the D810 at the 40% field position of the lenses. Does this mean that the 5D III has a higher resolution than the D810 between 40% and 100% of the given lenses?