I was trying to get my head around the DOF for my custom optics design and sadly it seems I end up with strange situation that the Near DOF value is larger than the far one making my DOF value negative. Is that correct?
Here are the details of my system. I have camera sensor of the following dimensions (7.4mm width, 5.55mm height, 9.25mm diagonal) and of 0.8um per pixel resolution.
I am using a lens of 30 mm diameter and 50mm focal length with fstop number of 1.67
Aperture diameter used is 10mm, therefore the Fstop of the optical system is 5.
As I am not printing the images taken but save them as PNG files, therefore I assumed circle of confusion to be the diagonal of the single pixel in the output image based on the sensor size this would be 0.00113um.
My hyperfocal distance ends up being 442527.8761mm (not sure if that is correct)
My DOF near seems to be 100.0113mm My DOF far seems to be 99.9887mm
So in the end my DOF ends up being: -22.5974um. For clarity I am looking for DOF >10um for microscopy imaging.
Please let me know if that is correct or is any of my assumptions and/or calculations wrong?