Did Hasselblad play any games to get the base ISO on the X2D II to 50? I ran some photon transfer curves to find out.
I’ll plot both of those on the same graph and add a horizontal line at Bill Claff’s Photographic Dynamic Range threshold:
Not much difference.
It appears that there are no tricks. I ran the sample set up very close to saturation so that we could see if there are any significant departures from linearity near full scale. There are not. The two x’s on the very right of the graphs are the result of what happens when the photon noise makes the signal clip, and that increases the signal to noise ratio. You can ignore that here, but I wanted ot make sure we got the mean signal levels as close to fullscale as I could, and those extra x’s are diagnostic.
Modeled full well capacities and read noise.
Ignore the middle column, unless you’re particularly interested in photon transfere curves. The data for that column was optained by using sime long shutter speeds, and the noise from those skewed the results.
The FWC is areound 55000 electrons at ISO 50. That is abotu a one third stop improvement over the X2D Mark I.
Good show, Hasselblad.
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