My Sony Pixel Shift artifacts-free Workflow
I do love the Foveon sensor.
I love the rendering of the not debayered images, the quality of fine details.
But I also love the photography and having a camera limited by 200/400 iso, with a different workflow and many limits gives me low chance to use it as I would like. In the last days I had a friend visiting me here in London, and strolling around the City during the night, free to test various shot configurations was a great chance to test new way to work; one of this was the Pixel Shift on my A7r3, the famous DEBAYERING mode so tricky to use.
Was great to use it having at the side the “monster” p45+ of my friend, in order to test some combined composition to be able to find any possible difference.
Having the files in my hands the mission was one and one only, to be able to work with pixel shift in the easiest possible way, sorting out the main problem of the technology, the artifacts of movements with no more than 5 clicks on a solid workflow (no manual masking etc).
I created a process for artifacts-free Pixel Shift files !
That’s what I did , compared to the original single raw at 200% and 400% (to show the detail on the right is not moirè but the resampling limit of the viewer)
Found the ideal workflow, was the turn of the comparsions: single raw file vs Pixel Shift file vs Phase One p45+ file.
Before that is important to remember the different size of the sensors:
As you can see, we are comparing 1800mm^2 with a 860mm^2 sensor; 16bit raw vs 14 bit raw.
This is the result of the test, in the upper part the Sony raw and Pixel shift, in the bottom the Phase One.
Both Sony and Phase one raws are light sharpened, the PS sample is without any further sharpening or NR after the processing.
No color processing was applied as you can see by the chromatic difference.
The difference is there, and the performance of the old lady Phase One is matched.
Below there are more samples crops of the original raw vs Pixel Shift.
Yes, some crops are 100%, some 200%.
Do not forget the raw was sharpened, the PS not, giving us a cleaner starting point for our workflow.
Someone could say :” I can’t see any dramatic difference”.
Yes, is not dramatic but is there; if you want the maximum quality from your equipment, your Sony a7r3 with a very good prime can give you a striking performance, close and sometimes even better than a REAL medium format camera with the feeling of a legendary Foveon sensor.
How to achieve that without artifacts?
I found a workflow for our Sony A7r3.
-Sony Imaging Software
-RawTherapee (free software)
-A very good quality tripod to get the four different shots required by our pixel shift workflow.
-My downloadable profile for RawTherapee
-Shot your four pictures and create with the sony imaging edge , the ARQ file (container for the four pictures)
-Open the ARQ file with RawTherapee , apply my profile ensuring the button on the side of profiles list is on “preserve mode”
-Adjust some light and shadows recovery as your taste and select in the demosaicing menu what sub-image for basic correction to keep.
-Export the final tiff Pixel shift file.
You can buy my profile for just 9 £!
Below is a FULLREZ sample of a A7r3 picture with a Nokton 40 1.2 with Pixel Shift.