## 5 Discussion: What to Care about When Designing, Developing, and Experiencing Holographic Showcases
In APM and BCM, several problems occurred, since the MR solution did not have too much space at its disposal and due to the contiguity with other multimedia, which made the environment noisy. In HNM, the set-up was perfect in terms of audio diffusion, as was that in LVR, where earphones were used (but this opened up other problems, like the reduced number of people that contemporarily could listen to the storytelling). * For the UXA \"Visibility and Appearance\", it is important to care about the following:
* Good illumination of the object inside the holographic showcase is a relevant issue for letting users fully experience the beauty of the real museum object. When such a condition was not guaranteed, the visitors did not appreciate the storytelling either, as the CQT and QQT revealed;
* It is necessary to follow a thoughtful design for the height of the window of the holographic showcase to suit all visitors' statures (e.g., children, elders, and families). In APM, BCM, and LVR, children were not able to see the digital contents, obliging their parents to pick them up;
* Glass protection from reflections is needed for avoiding external interferences with the holographic effects happening inside the showcase;
* A big holographic showcase seemed to work better than a small one in terms of narrative potential and involvement of groups of users, as the set-up in HNM and the OBS, CQT, and QQT revealed. * Leave a sufficient free space in front of the holographic showcase (at least 1 m of distance) for users to prevent them from seeing the trick of the [PERSON]'s ghost set-up;
- Provide seats for users (especially children and elders). Users want to rest in front of multimedia, especially if it is not interactive. This influences the perception of the story's duration and overall appreciation, as the CQT and QQT revealed;
- Provide diffused audio whenever possible or several Bluetooth headphones to let more people enjoy the holographic show. The soundscape quality was greatly appreciated by users and also expected, as visitors reported in the QQT;
- It is important to avoid waiting for language selection and provide a simple user experience in order to not frustrate users with multiple functions and an unclear system interface. This aspect was detected during the OBS and CQT; 5. For the UXA \"Environment and Plus Conditions\", it is important to remember the following:
- Do not exhibit too much multimedia close to each other, because they can conflict in terms of audio and users' tolerance (like what happened in BCM);
- Take care to ensure an efficient visitor flow, because crowd or noise situations may interfere with the user experience of the holographic showcase. This happened in BCM and APM, and the CQT, QQT, and OBS confirmed this negative trend;
- A dedicated space that is semi-dark and quiet for the holographic solution would be better, given the purpose of stimulating emotional intelligence to understand and virtually relive the past. Only in HNM was this guaranteed;
- In addition, create an integrated communication strategy for multimedia. Mention their presence along the museum visit path in the catalogue or in the museum guided tour, as well as through signals and visual graphics. None of the CEMEC venues fulfilled this task, but it is highly recommended for the next generation of MR solutions in museums. 6. For the UXA \"Audience\", it is important to remember the following:
- The entire museum experience highly influences the user's interaction with technology due to the time at their disposal, the museum visit path, the crowd, the flow, and the type of experience (alone or in a group);
- Storytelling was confirmed to be the most powerful way to involve the public when in front of the holographic showcase (and digital applications for communication in general);
- It is fundamental to improve the dialogue between curators and creatives. It is important to take care of the results of the user experience to improve the technological solutions from time to time.