  In recent years 360$^{\circ}$ videos have been becoming more popular. For
traditional media presentations, e.g., on a computer screen, a wide range of
assessment methods are available. Different constructs, such as perceived
quality or the induced emotional state of viewers, can be reliably assessed by
subjective scales. Many of the subjective methods have only been validated
using stimuli presented on a computer screen. This paper is using 360$^{\circ}$
videos to induce varying emotional states. Videos were presented 1) via a
head-mounted display (HMD) and 2) via a traditional computer screen.
Furthermore, participants were asked to rate their emotional state 1) in
retrospect on the self-assessment manikin scale and 2) continuously on a
2-dimensional arousal-valence plane. In a repeated measures design, all
participants (N = 18) used both presentation systems and both rating systems.
Results indicate that there is a statistically significant difference in
induced presence due to the presentation system. Furthermore, there was no
statistically significant difference in ratings gathered with the two
presentation systems. Finally, it was found that for arousal measures, a
statistically significant difference could be found for the different rating
methods, potentially indicating an underestimation of arousal ratings gathered
in retrospect for screen presentation. In the future, rating methods such as a
2-dimensional arousal-valence plane could offer the advantage of enabling a
reliable measurement of emotional states while being more embedded in the
experience itself, enabling a more precise capturing of the emotional states.
