Collimation profile of 3C 84 showing the jet width as a function of de-projected distance from the jet apex for the 2013 and 2016 measurements using the core shift constraint based on the jet–counter-jet distance. For the latter, we plot the collimation profiles obtained from both the clean image and the ehtim image. The jet width is measured as the separation between the edge-brightened structures of the jet. The closest measurement to the jet apex in 2016 is at ∼1560 r_g, where the jet width is ∼290 r_g. We fit the profiles with a power-law, and the resulting power-law index is a = 0.44 ± 0.07, indicating a parabolic profile similar to that of M 87.