Phase-contrast image artifacts
ID: phase-contrast-image-artifacts
A finite phase plate also intercepts diffracted light, altering low spatial frequencies. Halos and shade-off can therefore mimic borders or obscure interiors.[ref]
Introduction to Phase Contrast Microscopy by Nikon Instruments Inc.. Interpretation of Phase Contrast Images, halo and shade-off
In the coherent zero-mode model of phase contrast, the separation is perfect by assumption, so that model cannot predict those artifacts. New to topics? Read the docs here!