a7x, a9 PDAF stripe noise technical analysis, part deux

Started 10 months ago | Discussions thread
OP JimKasson Forum Pro • Posts: 22,286
a9 mean row sigmas

JimKasson wrote:

Horshack wrote:

JimKasson wrote:

The a7RIII longitudinal standard deviation image (512 captures this time), look quite different from the a9. The ones in this post are gamma-corrected and then histogram equalized.

I'm not sure what to make of this.

The row and column-wise histograms do look similar to the a9:

Thanks Jim. I'm not certain either. If I had to guess I'd say the seven vertical columns relate to the different parallel readout architecture of the A9 (higher frequency, perhaps needed to support the reported 12 rows being read in parallel). For the horizontal striping differences I'm guessing the higher density of PDAF rows perhaps combined with the baseline read noise differences. Can you compare the sigma of a single PDAF row between both sensors, and also an adjacent non-PDAF row to see the relative difference.

I can do better than that:

I'll have to go back and do the a9 for a comparison. That'll have to wait for tomorrow.

Here is the equivalent a9 graph:


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