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The wavefront Aberrations window is shown in Figure 1.

Figure 1 Wavefront Aberrations. The plotted function is the
contrast transfer function squarred and the 2-D CTF.
The wavefront Aberrations controls are placed in the following panes:
- Aberrations, to set wavefront Aberrations up to order 8. The effects of the wavefront Aberrations
on the 2-D contrast transfer function (2D-CTF) or the CTF squared are shown.
- Coherence, to change the CTF damping envelopes (Fig. 2).
- Drift & Noise, adds drift and vibration to the CTF (Fig. 3).
- Microscope, to control the objective lens aperture diameter, the convergence of the illumination,
the Chromatic aberration and the accelerating voltage in the Controls set 1 pane and the defocus step (defocus between 2 images) and
the Thermal Magnetic Noise amplitude.
- Shift & tilt, to set the phase shit produced by a phase plate on (000) and a possible illumination tilt.

Figure 2 Wavefront Aberrations window. The plotted function is the
contrast transfer function with the envelopes of partial spatial and temporal cohrences.
Notes
- The wavefront aberrations Wij are used by jems since they are at the origin of the image aberrations. The equivalent notations
of Krivanek and Haider are listed in Fig. 3.
- A popup menu is attached to either the CTF2 function or the 2-D CTF. It can
be used for example to labels the circles or to do rotational averaging (Fig. 4).

Figure 3 Notation of image and wavefront aberrations.

Figure 4 2-D CTF with labelled circles and rotational averaging.