Table 2.

Additional experimental conditions.

Experiment Number	A1	A2	A3	A4	A5
Phantom model	TF-ba	TF-dc	TF-bm	TF-bm	TF-bm
Corresponding patient age	55	2	55	55	55
Number of markers used	5	5	5	5	5
Movement speed	High	High	Low	Low	High
Ambient lighting	Medium	Low	Low	Medium	Medium
Microscope light	High	Medium	Medium	High	High
Comments	1. External object (wire) was introduced between 3 and 4 minutes2. Big jerk was applied at 2:15 minutes requiring re-registration	—	—	1. External object (needle) was introduced between 3 and 6 minutes2. Liquid ink was at introduced at 5 minutes	Liquid ink was present throughout the experiment

Additional experimental conditions. The experiments were performed for a duration of eight minutes each, using fiducial markers as reference points for evaluation. During experiments, translations, rotations and pitches were applied to the microscope. Further details on temporal bone phantoms are available at https://www.phacon.de/en/hno/felsenbein.