*4.1. General Impressions*

All the participants received the interactive multimodal guide and tactile exhibits well. The first impression of the IMG was much more exciting for the participants. They expressed surprise since, for most, it was the first time to use such a system, while reading tactile graphs was something they had already experienced. They eagerly expressed their desire to use both tactile graphics and IMG frequently at art galleries, and museums (Table 4-S1) and even demanded it, with expressions such as *"EP13: I can't understand why these (tactile graphics) are not available everywhere for every single artwork."*.

The IMG was considered extremely easy to use (Table 4-S3), mostly for two reasons; because it requires almost no effort to start using it, *"EP7: With this exhibit (IMG) you can feel the artwork from the beginning, you touch it, and it automatically starts telling things to you."*, and because it is easier to access and confirm information about their point of interest in the artwork directly *"EP11: I think one of the advantages is that with the speaking model (IMG), I can check what I'm touching by tapping two times right there, it is immediate. With the other one (tactile graphics), I need to go and read the Braille and come back, and sometimes I get lost in the graphic or with the Braille."* Having to switch between the Braille annotations, texture

legends, and the tactile graphics was perceived as the largest factor to perceive the tactile graphics as unnecessarily complex (Table 4-S2).



SUS score range from 1 ("Strongly disagree") to 5 ("Strongly agree").

Participants found the functions of both approaches well integrated (Table 4-S5). Participants were already used to exploring tactile graphics accompanied by Braille annotations. The simple touch interface on the artwork relief of the IMG coupled with the localized audio descriptions was well received. The participants expressed that hearing the localized audio while touching the 3D model area helped them to create a better spatial image of the shape and location of the object to the canvas. A couple of participants perceived background music.

One of them reported two effects; the first was that it made them think about the atmosphere of the scene in the artwork and the second was that it made her wonder about the time and circumstances that the artwork was made. *"EP8: When I heard the Korean traditional background music of the painting (Figure 3d) I could feel the solemnity of the painting and I wondered if the painter felt that way when making the painting"*.

All the participants expressed feeling very confident when using the IMG (Table 4-S10) because they could always revisit the points of interest quickly and trigger the audio descriptions or sounds to confirm the object that they are touching. For the tactile graphics, the opinion was divided between participants that felt very confident and those that didn't

because of the uncertainty of not being sure that they were correctly identifying the point of interest.

In general, the IMG was less cumbersome to use compared to the tactile graphics exhibit (Table 4-S8). Participants stated the following reasons: the difficulty of Braille, *"reading Braille is more difficult than listening to a conversation"*, the cognitive load of switching between the tactile graphic and Braille annotations: *"touching the object and getting its information is much better than having to read through Braille text and tactile graphics."* which adds up with each session: *"after trying several tactile graphics and Braille notes I felt more tired."*.
