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In reading about your 4x5 camera back, I think the plastic lens mount might be obstructing the light going to the sensor, the angles inside such a wide format s

In reading about your 4x5 camera back, I think the plastic lens mount might be obstructing the light going to the sensor, the angles inside such a wide format system are fairly large. If possible, I'd suggest removing it. As far as I can tell, there's no lens array on the sensor[1][2], just a normal Bayer filter. You could get a calibration frame by removing the lens with the sensor centered, and a black frame by putting a lens cap on, to help with corrections. That looks like a really fun project. With the HDR mode of the sensor you should get some awesome images. Good luck! [1] https://www.sony-semicon.com/files/62/pdf/p-13_IMX477-AACK_Flyer.pdf https://www.sony-semicon.com/files/62/pdf/p-13_IMX477-AACK_F... - (PDF) Flyer [2] https://www.uctronics.com/download/Image_Sensor/IMX477-DS.pdf https://www.uctronics.com/download/Image_Sensor/IMX477-DS.pd... - (PDF) Data Sheet

dheera 3y ago
Thanks! > I think the plastic lens mount might be obstructing the light going to the sensor It's actually a low-profile, 3D printed thing housing a glass UV/IR cut filter. The housing is flush with the glass filter unlike the stock Pi HQ camera lens holder. Removing the UV/IR cut results in full-spectrum photos that manifest the same color shift problem which is characteristic of CRA optimization (where they deliberately put the microlenses off-center toward the edges of the sensor. > As far as I can tell, there's no lens array on the sensor[1][2] I thought there is a lens array on almost all Sony sensors? [2] for example lists a "CRA characteristics of recommended lens" section on page 47, but this is not the full datasheet and only goes upto page 25. I can't find the full datasheet on the public internet unfortunately.
- mikewarot 3y ago
  Well, if you want to try something different, here's a modified camera that removes the microlens array along with color filters to make the sensor monochrome.[1] [1] https://maxmax.com/maincamerapage/uvcameras/raspberry-pi-hq-12mp https://maxmax.com/maincamerapage/uvcameras/raspberry-pi-hq-...
  - mikewarot 3y ago
    Alternatively, you could tilt the sensor as you move it to compensate. Perhaps moving it on a curved path to match the optical center? I don't know how well that would work with variable focal length lenses, though. If you've ever seen a ball cutter attachment for a lathe, or one of those parallax eliminating camera mounts, you could step the sensor along a sphere instead of a plane.

dheera 3y ago

Thanks! > I think the plastic lens mount might be obstructing the light going to the sensor It's actually a low-profile, 3D printed thing housing a glass UV/IR cut filter. The housing is flush with the glass filter unlike the stock Pi HQ camera lens holder. Removing the UV/IR cut results in full-spectrum photos that manifest the same color shift problem which is characteristic of CRA optimization (where they deliberately put the microlenses off-center toward the edges of the sensor. > As far as I can tell, there's no lens array on the sensor[1][2] I thought there is a lens array on almost all Sony sensors? [2] for example lists a "CRA characteristics of recommended lens" section on page 47, but this is not the full datasheet and only goes upto page 25. I can't find the full datasheet on the public internet unfortunately.

mikewarot 3y ago
Well, if you want to try something different, here's a modified camera that removes the microlens array along with color filters to make the sensor monochrome.[1] [1] https://maxmax.com/maincamerapage/uvcameras/raspberry-pi-hq-12mp https://maxmax.com/maincamerapage/uvcameras/raspberry-pi-hq-...
- mikewarot 3y ago
  Alternatively, you could tilt the sensor as you move it to compensate. Perhaps moving it on a curved path to match the optical center? I don't know how well that would work with variable focal length lenses, though. If you've ever seen a ball cutter attachment for a lathe, or one of those parallax eliminating camera mounts, you could step the sensor along a sphere instead of a plane.