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03-19-2016, 01:14 AM   #16

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The calculation is not based on pixels but area. 24mp of the d800 is a larger area than 24 mp on the k3.

Imagine the same lens, same subject. It would once magnified by the lens occupy the same area in square mm on both sensors. The sensors have different pixel densities, so the resolution N is a different number.


This is a paste of the formula in Google sheets.
B2 is the SNR for the Iso from the dxo screen chart.
A38 is the crop fraction, 0.4.
B30 is the area of a FF sensor in sq mm.
B27 is the pixel density of the sensor in pixels/sq mm.
B4 is 8*300*12*300, or the pixel resolution of an 8*12 print at 300 DPI.

---------- Post added 03-19-16 at 01:20 AM ----------

I didn't do the chart for the K5, I should. The K5iis probably would be closer. I know the K3 allowed me to crop more than I did with the K5, but there were characteristics of the K5 sensor that were very nice. Pulling shadows, a different noise character. This chart doesn't really represent the full complexity of the sensors in question.

03-19-2016, 01:27 AM   #17

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QuoteOriginally posted by derekkite Quote
This chart doesn't really represent the full complexity of the sensors in question.
On your chart, K-3 @ 100 ISO as about 2dB better SNR than D800E @ ISO100 cropped. Collecting the same amount of light on the same sensor surface (APSC or cropped FF), where is the 2dB noise reduction of the APSC coming from?
03-19-2016, 03:44 AM   #18
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QuoteOriginally posted by jsherman999 Quote
Do we even know who that photog is though? It could also have been total luck for all we know, unless there's a back story to it.
Capa was embedded with the troops landing at Omaha Beach - he influenced the look of 'Saving Private Ryan'.

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