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MF Digital, myths or facts? - Are large pixels better?

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Article Index
MF Digital, myths or facts?
Collecting more photons
Comparing the top of the line MF back with the top of the line DSLR
Is Capture One better on IQ180 files?
A larger format is less demanding of the lens
The Really Right Stuff
OLP (AA) filtering
The 16 bit issue, truth or myth?
Do MFD have better DR?
MFDBs have better color, truth or myth?
Summary and conclusions
Are large pixels better?
Read also
Experts's comments
All Pages

Are large pixels better?

The way I see it small pixels are preferable to large pixels in most aspects.
Regarding the number of photons collected, the only factor that really matters is the number of photons collected. Smaller pixels would collect fewer photons, but there would be more pixels. It matters very little if you collect 24 000 000 x 1000 photons or 6 000 000 x 4000 photons you still end up 24 000 000 000 000 photons. Would you print the image at 8x10" at 360 PPI you would end up with 2300 photons/pixel in both cases.

Once a print scale is fixed photons/pixel in the sensor is irrelevant.

There is some relevance to pixel size regarding DR but none at all with regard to shot noise.

Now the above reasoning is not exactly correct, as there are electronic components and wiring associated with ecah pixel. Making the pixels smaller mean that more of the chip estate will be used for wiring and components. The optimal size of pixels shrinks when narrower design rules are used. Here is a good article on the issue.

Smaller pixels allow for higher resolution but they will also reduce aliasing artifacts. A sensor with smaller pixels will be of lesser need of OLP-filtering. A sensor with smaller pixels will have less jaggies and respond better both interpolation and deconvolution type sharpening.

Noise characteristics are much less dependent on pixel size than commonly believed, here is an excellent article discussing the issue.
Phase One has a technology called Sensor+ where four pixels are binned into one at high ISO. So the IQ180 goes from small pixels to large pixels when increasing ISO. The DxO data shows this quite clearly.
In the data normalized for a given print size, Sensor+ gives a small increase in DR.
The effect on "Tonal range" which is dominated by shot noise, the effect of increasing pixel size is ignorable.

Last Updated on Thursday, 13 December 2012 11:56  


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