[Brightcolours]

Your post does not make sense in two ways. First of all, about my 28mm f1.8. I said it is diffraction limited at f2.8. Which it is. And the figures I quoted were for a longer wave length (e-line), hence the lower diffraction limit number (536lpmm). I did not say it was diffraction limited at f1.8.

I did also not say that diffraction limits are dependent on something else than the aperture... The figures are related to the wavelength, though.



The 2nd part that makes no sense is your f11 figure for Nikkor 1 10 mp. The f-value where diffraction already takes its toll in resolution is demonstrably f8 for a Canon EOS 5D mk II. If we make the pixel pitch higher, we only will see the softening caused by the diffraction more clearly. Simply put: the projected image at f8 is softer than the projected image at f5.6 due to diffraction. And the 5D mk II has enough resolving power to detect this.



Those are the facts... diffraction effects getting to be measurable at f8 already for a 5D mk II with 6.4µm pixel pitch. And lower for 3.2µm pixel pitch.



It is basically talking about two different things then... In relation to Nikon 1 10mp, it will start to suffer from softer results due to diffraction at f4, and if we use smaller f-values, the image will resolve less and less. And with a 5D mk II we see a softer image at f8 than at f5.6 already.



Those are the numbers that matter, for us photographers.

http://web.ncf.ca/bf250/diffraction.html