Teoretyczna granica rozdzielczości zależy od szkła a nie od matrycy - matryca 18Mx ma większą rozdzielczość niż 12Mpix i tyle...Zamieszczone przez HuleLam
Zobacz "blur index" a ten dla f=16 na 35/1.4 http://www.slrgear.com/reviews/showp...uct/148/cat/10
http://www.slrgear.com/reviews/zarti...howwetest.html
One BxU (DxO's Blur Experience Unit) is equivalent to 1 application of the Photoshop Blur filter
Approximately (using 1 Bxu = 1 Blur),
MTF @ 0.25 cycles/pixel (half-Nyquist) = 0.862 * 0.78BxU).
MTF50 (cycles/pixel) = 1 / sqrt(6.067 BxU + 3.6)
Blur is the approximate inverse of Sharpen and that the number of Blur applications is proportional to 1/MTF502. Alternatively,
BxU is approximately equal to 4.6 * LSF variance (σ2) in pixels
To get more detailed:
blur is is equated with the variance (σ2 ) of gaussian blur, exp(-x2 / (2σ2 )). (This one dimensional equation is somewhat simplified. DxO uses two-dimensions: Blur = (σxx2 + σyy2) / 2 ). Since σ has units of distance, this suggests that BxU is proportional to the square of the 10-90% rise distance. And since the Fourier transform of a gaussian is itself a gaussian, this implies that BxU is proportional to 1/MTF502.
http://www.imatest.com/docs/blur_mtf.html
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