How to simulate defocused particle images?

I am looking for some kind of image generator to generate scattered images of particles at different defocus distances.
I tried to start with PSF and tried PSF-Generator. But it failed

Due to the intersection of forums, I posted the original post below.

Anyone with a comment is welcome! Thank you!

Thanks for the cross posting @CooperZZ, since there’s some discussion already, let’s encourage anyone here to contribute over on that post as well to keep the discussion in one place. I’ll post over therenow