Analysis of the Relationship Between Mural Content and Its Illumination: Two Alternative Directions for Design Guidelines

Abstract

As part of contemporary urban culture, murals support place making and city identity. While much attention has been paid to their role in activating public space during daylight hours, their presence after dark remains largely unexamined. This paper analyzes how mural content interacts with night-time illumination. The research draws on case studies, photographs, luminance measurements, and lighting simulations. It evaluates how existing lighting systems support or undermine the legibility and impact of commercial murals in urban environments. It explores whether standardized architectural lighting guidelines suit murals, how color and surface affect visibility, and which practices improve night-time legibility. The study identifies a gap in existing lighting strategies, noting that uneven lighting distorts intent and reduces public engagement. In response, a new design tool—the Floodlighting Content Readability Map—is proposed to support artists and planners in creating night-visible murals. This paper situates mural illumination within broader debates on creative urbanism and argues that lighting is not just infrastructure, but a cultural and aesthetic tool that extends the reach and resonance of public art in the 24 h city. It further emphasizes the need for interdisciplinary collaboration and a multi-contextual perspective—encompassing visual, social, environmental, and regulatory dimensions—when designing murals in cities.

1. Introduction

Artificial light plays a significant role in shaping and perceiving urban space (Sholanke et al. 2021). With the development of exterior lighting technologies, a new night-time visual identity of the city has emerged—one that should also be considered in the design process and in building the identity of specific urban areas. Until recently, most flat, detail-less building façades remained dark after dusk. This began to change with the evolving function of large-scale mural painting in the urban context. Today, murals have become a permanent feature of urban environments and increasingly contribute to the visual identity of cities after dark (Mendelson-Shwartz and Mualam 2021). They are commonly used as tools of urban revitalization, bringing color, vibrancy, and aesthetic value to otherwise dull or degraded areas (Zebracki 2013). Beyond their aesthetic function, murals also support community-building processes (Silberberg et al. 2013). Public art interventions are often designed to foster social inclusion (Sharp et al. 2005), yet in some cases, they are strategically integrated into municipal planning as part of a cultural infrastructure aimed at gentrifying targeted neighborhoods (Mathews 2010).

This type of painting is a convenient form of communication, intended to stimulate creativity (Bengtsen 2014) or to promote specific behaviors (Maevskaya 2022; Eltokhy et al. 2024), including consumer ones. During the daytime, the impact of artistic and commercial murals on urban space is usually not significantly different. Both types are characterized by defined color schemes, contrast levels, and compositional structures. The stylistic diversity of artistic and commercial murals also remains comparable. However, significant differences appear in how these murals function at night and thus in how they influence both the city and its inhabitants. Likely for economic reasons, only commercial murals are consistently illuminated. At night, the lighting of these multicolored surfaces can affect not only the visibility of the painted advertisement but also the overall emotional perception of the surrounding space (Ormeno Blanco and Arranz 2025).

The illumination of commercial murals is also relevant in the broader context of outdoor advertising. First, the light emitted from such installations impacts the environment. Light pollution can disrupt circadian rhythms in both humans and animals (Bumgarner and Nelson 2021), alter migratory behaviors (Burt et al. 2023), and has even been linked to serious health issues (Urbano et al. 2021). Additionally, poorly designed lighting can reduce road safety by distracting drivers—an effect already studied in relation to other forms of advertising (Glicz et al. 2013; Oviedo-Trespalacios et al. 2019) and typical outdoor areas (Skarżyński and Rutkowska 2023). It can be assumed that illuminated murals—both commercial and artistic—may pose similar risks as advertisements displayed on billboards (Wang et al. 2021) or digital screens (Zalesińska 2017). Given the growing prevalence of murals in urban environments (Mendelson-Shwartz and Mualam 2020, 2021, 2025), it is essential to conduct further research into improving their lighting design (Dubnicka et al. 2019). There is a growing need for general urban lighting guidelines (Araji and Boubekri 2011; Zielinska-Dabkowska and Bobkowska 2022)—particularly for illuminated murals, which require special attention to visual, informational, humanitarian, and ecological aspects.

Although murals can be temporary and subject to change, they require a permanent support structure, which is typically an architectural surface (Petronienė and Juzelėnienė 2022). Therefore, their illumination can be approached similarly to that of architectural objects. Urban night lighting schemes are increasingly studied for their aesthetic and functional impact after dusk (Liu and Li 2023). It follows that recommendations and standards established for building illumination may also apply. These guidelines specify recommended average luminance levels, depending on the brightness of the background or surrounding environment—CIE 094-1993; CIE 150:2017; CIE 234:2019 (Prieur et al. 1993; Pollard et al. 2017; Serefhanoglu Sozen et al. 2019), while regulations set upper limits for those values (EN 12464 2:2014 2014; EN 13201-2:2015 2015). However, it is important to note that a mural is, by definition, a semi-permanent or temporary form, and its legal and functional status differs significantly from that of a building (Animbom et al. 2024; Mendelson-Shwartz and Mualam 2020). Expectations for mural lighting also differ in key ways from those applied to architectural illumination. For this reason, lighting requirements for murals should be considered independently.

A mural lighting system should not only highlight color and composition but also ensure the clarity and legibility of its content. This pragmatic approach aligns with current research and curatorial practices related to the illumination of artworks in galleries and museums (Schielke 2019, 2020). In public space, the lighting of mural surfaces should be evenly distributed, and luminance levels should remain within recommended thresholds CIE 094-1993 (Prieur et al. 1993). This is relatively easy to achieve in the case of static, rarely altered artistic murals. In contrast, commercial murals pose a more complex challenge: as content changes over time, the reflective properties of the surface also change, while the lighting system typically remains unchanged. The issue of illuminating commercial murals under these dynamic conditions is the central focus of the present study.

Research Questions:

Q1. Should mural lighting follow the standards used for architectural illumination?

Q2. How does a change in color affect the average luminance level of a mural?

Q3. Are the lighting solutions currently used in urban spaces for variable commercial murals effective regarding legibility, aesthetics, and functionality?

Q4. Should illumination systems for commercial murals allow for adjustment, and if so, what types of changes are most desirable (e.g., intensity, color temperature, or direction of light)?

Q5. How should commercial mural compositions be designed to ensure content legibility under fixed lighting systems?

This article aims to address a gap in existing research: the lack of basic design principles for illuminated murals. These principles would help murals become coherent and aesthetically integrated parts of the night-time urban landscape. It is essential to develop basic guidelines, both for the lighting design of artistic and commercial murals. For advertising murals, content composition should take into account existing lighting systems.

The research methodology includes several stages: photographic documentation, measurement of actual luminance distributions of seven murals, and simulation-based analysis of various lighting systems applied to the side façades of buildings where the murals are located.

2. Structure of the Article and Course of Analysis

This article is divided into two main parts. The first section focuses on the analysis of an artistic mural. Its selection and the accompanying lighting simulation are intended to serve as a point of reference for evaluating building façades used for commercial murals, which are examined in the second part. This approach stems from the fact that artistic murals generally have a longer life cycle and, when illuminated, typically benefit from dedicated lighting systems that provide a brightness level sufficient to ensure content legibility. This section, based on theoretical simulations, addresses the first two research questions (Q1 and Q2).

The second part of the article is dedicated to the analysis of three neighboring building façades, regularly used by the same operator to display advertising murals that vary in form. Two of these surfaces are illuminated using conventional methods, but with different lighting configurations. The third employs multimedia projection. The diversity of lighting conditions enables a comprehensive comparative analysis and allows for answering the remaining research questions (Q3–Q5), as well as providing a practical verification of the theoretical assumptions related to Q1 and Q2. In total, we analyze commercial mural compositions and one artistic piece, placed on four walls in two different localizations.

3. The Mural in Daylight and After Sunset

3.1. Analysis I. Fixed Illumination of an Artistic Mural

Figure 1A presents a mural located in the vicinity of residential buildings (see Map 1), depicting scenes related to historical events. The mural is divided by cornices into five sections, each corresponding to a distinct theme. Each section has a different background color, transitioning gradually from dark green to light yellow–green. Across all sections, silhouettes of soldiers and military equipment are depicted in a consistent artistic style.

This mural provides a suitable basis for an analysis of how color composition affects the luminance distribution under daylight conditions, as well as for a comparison of those results with artificial lighting simulations carried out using computer modeling.The analysis was conducted in accordance with guidelines appropriate for building illumination. The primary viewing perspective was taken into account, and data was collected under favorable weather conditions to eliminate any potential distortions.

During the day, like any surface, the mural is illuminated relatively evenly by natural daylight. An analysis of the luminance distribution (Figure 1B) shows that the average luminance of the mural under daylight conditions is approximately 741 cd/m², while the luminance of the sky reaches about 5000 cd/m². Despite this reverse contrast ratio (1:6), the mural remains highly visible and effectively attracts attention. The situation changes drastically after nightfall. At that point, luminance levels drop sharply and become more uniform. If the surface is not illuminated with artificial light, it becomes practically imperceptible, losing both its informational and aesthetic functions. Figure 1C shows a photograph of the unlit mural, while Figure 1D presents the corresponding luminance distribution. At night, the wall is only partially detectable due to the reflective effect of metal cornice elements catching ambient light.

An analysis of the luminance distribution of both the sky and the building façade featuring the mural reveals that luminance levels are uniformly low, averaging around 0.3 cd/m². Due to this very low ambient luminance, and in accordance with CIE 094-1993 recommendations (Prieur et al. 1993), if the mural is to be treated as an architectural element, it should be illuminated to reach an average luminance level of 4 cd/m². This represents an inversion of the contrast ratio observed in daylight, with a comparable luminance ratio. Figure 2A presents a computer simulation of such a lighting scenario. Illuminated with a relatively low average luminance, the mural stands out clearly against the dark background, successfully attracting the viewer’s attention. The content presented on the mural remains legible. The illumination significantly and positively transforms the character of the night-time visual scene.

Following the presented simulation, the conclusion may seem straightforward: one might assume that a mural should be treated as an architectural object and that its illumination should follow the applicable guidelines and standards for architectural lighting. In such a case, the lighting design would simply require adjusting the luminaires’ output to match the content of the mural.

This approach is indeed appropriate—but only in the case of murals with a fixed composition. As previously noted, urban spaces are dominated by commercial murals, the content of which changes frequently. According to the authors’ observations, in some cases, the artwork is replaced as often as every two weeks. This raises a critical question: how should such variable-content murals be illuminated?

3.2. Analysis II. Illumination of Commercial Murals

Figure 3A shows the gable walls of three adjacent buildings in the centerof Warsaw (see also Figure 3C). All three façades are managed by the same company, which regularly produces a variety of commercial murals on them—sometimes combining them into larger, interdependent compositions. This location offers a rare opportunity to compare different lighting strategies under similar urban conditions. The murals are lit using several distinct approaches: indirect lighting from a nearby streetlamp, bidirectional lighting, and single-sided lighting from above and one side. Presenting these diverse lighting conditions in a single photograph enables a more comprehensive comparison of the effects produced by each technique. The murals themselves (Figure 3A) differ in both content and brightness. The first, on the left, features a rose on a solid light-grey background and advertises a clothing brand. The second and third murals promote a sportswear company. The central mural contains a large headline, a white sneaker, and the company logo. The third mural is the darkest: at first glance, its content may be difficult to discern. It depicts a dark-haired figure dressed in black against a black background. Despite these considerable differences in composition brightness, all three murals exhibit excellent visibility in daylight and fulfilltheir intended function—they are visually engaging and attract attention.

Only a careful observer, while walking along the street, may notice that an additional factor differentiating the murals is the texture of the walls and the type of painted surfaces, which range from matte to glossy finishes. These surfaces exhibit different reflective properties resulting from the use of varied materials and painting techniques, making these murals a particularly interesting subject for observation. An analysis of the luminance distribution under daylight conditions (Figure 3B) reveals that the inverted daylight contrast approach, identified as suitable in Section 3.1, does not apply effectively in this case. Although the average luminance of the sky remains the same as in the case of the artistic mural, the first commercial mural shows an average luminance of approximately 10,000 cd/m², the central one around 4500 cd/m², and the third about 2000 cd/m².

The three murals shown have a distinctly commercial character. Their illumination should therefore ensure that they fulfill their intended function throughout the entire day and night cycle. They are expected to draw attention, but without significantly distracting drivers (Beijer et al. 2004) or causing blinding glare—or even discomfort glare (Fotios and Kent 2020). As such, luminance levels and contrast ratios should not be excessive. The content should remain legible, and colors should not be distorted.

A photograph taken after dark (Figure 4A) shows that, in various ways, all three murals lose clarity. The mural with the rose is illuminated only indirectly by a nearby streetlamp. The central mural is lit from both sides and from above; however, the fixtures are unevenly spaced vertically, resulting in underexposure in the lower section of the mural (below the first cornice). The third mural is illuminated only from one side and from above, using a single luminaire. Additional ambient light comes from a nearby streetlamp. Under these evening conditions, the exposure of all three murals is inconsistent (Figure 4A), which is further confirmed by the luminance distribution analysis (Figure 4B).

The measured average luminance levels vary significantly: the first mural, which lacks dedicated lighting, has an average luminance of about 1 cd/m²; the central mural reaches approximately 8 cd/m²; and the third mural measures around 3 cd/m².

The analysis shows that none of the presented lighting setups meet the recommended average luminance levels for architectural objects situated in bright surroundings. The recorded values fall below the minimum of 12 cd/m², as indicated in CIE 094-1993 (p. 9) (Prieur et al. 1993).

Notably, the final value remains low despite the use of a glossy surface material. Due to the type and direction of the lighting, this surface displays the greatest and most problematic variation in illuminance. It can be assumed that the glossy finish was intended to increase overall luminance. However, the result is the opposite: the mural exhibits glare and reflections (originating from both the dedicated lighting system and the streetlamp), which—depending on the viewing angle—obscure the content and compromise legibility.

Luminance is closely linked to the reflective properties of the material. Emulsion-based (latex or acrylic), spray-applied acrylic paints, oil paints, and textured plaster all reflect light differently. As the content of these murals changes frequently (on average, once a month), it is possible to encounter a configuration in which murals with different lighting setups achieve the same average luminance level due to differences in content and materials.

The first mural, regardless of its visual content, will always remain poorly visible after dark due to the absence of a dedicated lighting system mounted on the building façade.

The same average luminance can also be achieved by adjusting the luminous flux of the light sources. Let us assume a hypothetical scenario in which the installed luminaries are equipped with such functionality. Figure 4A,B presents a computer simulation of two murals illuminated to achieve the same recommended average luminance level of 12 cd/m², with glossiness eliminated from the surface of the third mural.

An analysis of the luminance distribution shown in Figure 4C,D reveals that the equalization of average luminance was achieved primarily by increasing the luminance of the brightest areas of the murals. In the case of Mural No. 3, this resulted in a loss of color saturation. The maximum luminance values reached 100 cd/m², which negatively affects content perception. It can therefore be concluded that attempting to equalize average luminance across murals located in close proximity is not an effective solution. This is also illustrated in a lighting scenario for the first mural, in which a constant luminance of 12 cd/m² is maintained using a multimedia projector (Figure 4E). In this case, Mural No. 1 stands out significantly compared to the others, despite having lower contrast values. The murals differ notably in background color and tonal balance, creating a strong contrast between them—even when average luminance levels are kept equal. As a next step, we reversed the color schemes of Murals No. 2 and No. 3 to test how composition contrast affects perception under uniform average luminance. Figure 4G,H presents a computer simulation of this scenario. In this simulation, although each mural maintains the same average luminance level of 12 cd/m², the central mural (No. 2) appears to be the brightest. One might initially attribute this to high luminance unevenness, but this hypothesis does not hold. In fact, Mural No. 3 has the lowest uniformity in both illuminance and luminance, due to its single-sided lighting and additional input from a nearby streetlamp, whose luminous flux output cannot be regulated. Why then does the central mural appear brightest? The answer lies in the contrast inits visual composition and the recommended average luminance levels for the mural’s urban context—namely, a city center. This raises a new question: are the standard luminance recommendations for architectural objects too high when applied to murals?

Figure 5A presents a photograph and actual luminance measurements (Figure 5B) for an alternate content configuration of Murals No. 2 and No. 3, taken under conditions where Mural No. 1 was illuminated using a multimedia projector. The average luminance across all three murals was balanced and fell within the lower limits recommended by CIE guidelines and architectural lighting standards. The measured average luminance values are as follows: Mural No. 1 (L1): 3.87 cd/m², Mural No. 2 (L2): 4.25 cd/m², Mural No. 3 (L3): 4.15 cd/m².

Despite the equalized average luminance across the three murals, in this scenario, it is Mural No. 3 that draws the most attention, while Mural No. 1 still appears underlit. Once again, this effect is primarily due to high luminance contrasts resulting from surface material properties. However, the overall perception of brightness across all three murals is more balanced than in the previous scenario. This suggests that, in the case of murals, the standard average luminance values recommended for architectural objects are not always applicable. What proves more important is achieving the most uniform illumination possible. When uniform lighting cannot be ensured, the composition should be designed with knowledge of the lighting’s non-uniformity in mind—allowing the luminance levels to be adjusted accordingly to fit the mural’s layout. This thesis is further supported by another measurement taken after the content of Mural No. 1 was changed (Figure 5C,D). Despite the use of materials with lower reflectance coefficients, the mural—illuminated by a multimedia projector—achieved a higher average luminance level of 7.5 cd/m². Interestingly, this value is nearly twice as high as that of the other two murals, yet the human eye does not perceive it as significantly brighter. The perceived brightness of all three murals is similar.

Why is that? The answer lies in the maximum luminance values and the surface areas with high reflectance. The luminance distribution, measured using a matrix luminance meter (which does not represent the content clearly or directly), shows that the areas with the highest luminance (marked in red) form a cohesive visual composition in Murals No. 1 and 2. Mural No. 3 is slightly more isolated—both visually and physically—due to the presence of residential space separating it from the others (and also located behind the mural).

3.3. Luminance or Illuminance?—That Is the Question

Both the standards and recommendations for object illumination refer primarily to luminance. However, the mural lighting analysis presented herein demonstrates that designing lighting systems based solely on luminance is a risky approach. This raises an important question: should illuminance—rather than luminance—serve as the main design criterion for mural lighting? Let us examine this parameter using the example of the three façades, each lit by a dedicated lighting system providing a consistent average illuminance level of 50 lx with high uniformity. With an average reflectance coefficient of 0.8, this level of illuminance results in an average mural luminance consistent with recommended values. In the case of a plain white wall (prior to mural application) under the same lighting conditions, the luminance would be uniformly 12 cd/m². After nightfall, the perception of any murals painted on these surfaces would then depend primarily on their visual composition—much like how they are perceived during daytime hours.

But is this truly an optimal situation? A mural with the brightest composition on such asurface will naturally attract more attention than the others. Therefore, when illuminating murals located in close proximity to one another, it is particularly advisable to use lighting systems with independent luminous flux control for each mural. With such a system, it becomes straightforward to adjust the average luminance of each mural to the same target level. The remaining consideration, then, is the choice of the target luminance value—in this scenario, 12 cd/m².

3.4. Illuminance or Luminance Uniformity?

In principle, the illuminance uniformity on a mural surface should be as high as possible. However, achieving this is not always feasible in real-world conditions. Does this limitation necessarily prevent achieving a balanced luminance level? Luminance is a photometric parameter dependent on both the reflectance coefficient and the nature of surface reflectance. Therefore, it is influenced directly by the mural’s composition. This knowledge can—and should—be used intentionally in the design of illuminated advertising surfaces. In underlit areas, it would be advisable to use pigments with a higher reflectance coefficient, while in overlit sections, darker colors should be applied.

If the mural has already been illuminated and such an analysis was not conducted during the lighting design phase, it is necessary to measure the luminance distribution using a matrix luminance meter before the mural is painted. Based on the resulting luminance map, one can identify areas that require different reflectance coefficients—this forms the basis for creating a so-called Floodlighting Content Readability Map (Figure 6, step V). In this map, black areas indicate zones where materials with high reflectance should be avoided. This provides a foundation for developing advertising content that, once illuminated, will be both legible and visually appealing to the human eye. It should be emphasized that this map serves only as a guideline for balancing luminance levels across the mural. In many commercial compositions, it may be desirable to deliberately vary focal points in order to direct the viewer’s attention. In such cases, the brightness map of the composition can also serve as a valuable design aid, especially when deliberate focal points are intended.

4. Conclusions

This study has successfully provided comprehensive answers to all five research questions formulated at the outset.

Q1.Should lighting design for murals follow the standards and guidelines currently applied to the illumination of architectural objects?

Partially. While architectural lighting standards (e.g., CIE 94) provide a useful reference, murals—especially commercial and variable ones—require separate treatment due to their visual, functional, and material diversity.

Q2. How does a change in color affect the average luminance level of a mural?

Color changes significantly influence luminance, especially under artificial lighting. The same lighting system can produce different luminance levels depending on the brightness, hue, and surface texture of the mural composition.

Q3. Are the lighting solutions currently used in urban spaces for variable commercial murals effective in terms of legibility, aesthetics, and functionality?

In most observed cases—no. The analysis showed that current systems often result in overexposed or underlit areas, compromising legibility and undermining both aesthetic and communicative goals.

Q4. Should illumination systems for commercial murals allow for adjustment, and if so, what types of changes are most desirable?

Yes. Adjustable systems are highly recommended, especially in contexts where mural content changes regularly. Most desirable features include the ability to control light intensity, direction, and distribution—ideally integrated with content-aware strategies.

Q5. How should commercial mural compositions be designed to ensure content legibility under fixed lighting systems?

Compositions should be informed by the specific lighting conditions of the surface. Designers should consider using Floodlighting Content Readability Maps to match contrast, color, and reflectance properties to illumination variability. In darker areas, high-reflectance pigments are recommended, while in overlit zones, darker tones should be used.

Murals are not merely decorative elements but contribute meaningfully to urban identity, night-time aesthetics, and socio-cultural communication. As demonstrated by this study, they function as fully integrated urban elements—deserving the same level of design attention as architecture or public infrastructure. Yet, existing lighting regulations and urban design guidelines provide neither sufficient standards nor practical tools for assessing or designing appropriate illumination systems for murals. This gap highlights the urgent need for greater interdisciplinary awareness among policymakers, urban planners, and design professionals. Without such attention, mural illumination risks remaining inconsistent, inefficient, and visually ineffective—undermining its communicative value and contributing to unnecessary environmental impact.

Illuminating murals in a way that does not ensure clear and uninterrupted visibility of their content appears counterproductive. First, such murals may become illegible. Second, they may reduce drivers’ concentration. Third, financial and energy resources are wasted, while light pollution unnecessarily degrades living conditions for both people and animals (Widmer et al. 2022). Although modifying lighting systems is technically possible, it is more complex and requires more advanced luminaires capable of regulating luminous flux.Although the cost of replacing luminaires is a valid consideration, it should not be viewed as a major obstacle given the overall improvement in readability. Ideally, before changing the content of the mural, the lighting setup should be simulated in advance by a specialist. However, this would require advertising companies to collaborate with lighting professionals and use dedicated design software. Such an approach would enable designers to achieve even luminance levels across murals and, importantly, prevent overexposed areas in mural compositions. It is advisable to aim for a uniform illuminance of up to 100 lx, with adjustable luminous flux that allows mural luminance to fall within the range of several to a dozen cd/m²—depending on the visual design.

The approach proposed in this article offers an alternative and accessible path. The findings show that night-time legibility of visual compositions depends not only on lighting levels but also on the thoughtful integration of content, color, and material properties into the lighting conditions of each specific site. To address this, we propose anew type of pre-design analysis: the Floodlighting Content Readability Map. Importantly, murals are not merely visual decorations—they function as tools for revitalization, place identity, and public communication. Poor lighting can distort or erase that function. When properly illuminated, murals contribute to urban aesthetics, increase the attractiveness and cohesion of public space, and support community engagement. Failing to consider their legibility after dark weakens their social and cultural impact.

Designers should also account for the maximum luminance values on murals and the surface area they affect. In some cases—depending on visual composition—the mural with the lowest average luminance may paradoxically attract the most attention. The authors intend to explore this phenomenon in future studies. The effectiveness, time-efficiency, and cost-efficiency of two alternative lighting strategies—adapting the lighting system to changing content or vice versa—should be subject to further evaluation. We also call for neuro-architectural research using eye-tracking to explore how different mural lighting schemes affect the visual behavior of pedestrians, cyclists, and drivers (Vetturi et al. 2020). Current CIE regulations (Prieur et al. 1993; Pollard et al. 2017; Serefhanoglu Sozen et al. 2019) are insufficient for managing urban visual environments in a sustainable way. Municipalities could adopt local mural and advertising lighting policies to reduce visual clutter, limit unnecessary artificial lighting, and harmonize administrative processes. However, due to the scope of the issue, we argue for internationally coordinated guidelines. Considering the typical costs, timeframes, and administrative complexity associated with implementing such regulations, this should be viewed as a long-term strategyfor existing lighting installations. For newly designed spaces, it is recommended to use luminaires with adjustable luminous flux. Currently, their cost—depending on the manufacturer—is no more than twice that of traditional fixtures. Because murals typically use a small number of light sources, the overall installation cost remains relatively low. In the short term, meaningful improvements can be achieved by adjusting design processes and upgrading existing lighting infrastructure. Therefore, immediate efforts should focus on informing designers, lighting manufacturers, and commercial mural administrators.

The solutions presented in this article are suitable for any mural location, height, or road width, as the luminance distribution is independent of these parameters. Even in areas with only pedestrian traffic, the readability of the illuminated mural should be maintained, and the illumination values should be adjusted to recommendations and standards. This situation can be applied to building lighting to some extent, but with certain limitations. Standard architectural lighting norms are difficult to apply to large-scale, high-contrast compositions typical of murals. We recommend that future CIE guidelines provide dedicated, context-sensitive recommendations for mural illumination. This is essential for building safe, legible, and visually cohesive urban spaces.

Considering the night-time appearance of a mural as equally important as its daytime version may initially be perceived by artists as a limitation of their creative freedom. Technical requirements related to illumination can affect how the composition appears, even during daylight. From the advertisers’ perspective, however, this would be an advantage—offering a more consistent visual message around the clock. For viewers too, it could enhance the aesthetic quality of the space, as thoughtful lighting contributes to a more cohesive and visually engaging environment after dark.

Finally, architectural, art, and design education should include greater emphasis on lighting awareness—not necessarily to train specialists, but to foster interdisciplinary sensitivity and environmentally responsible thinking. This awareness should naturally lead to the inclusion of lighting design professionals in the development of urban visual communication projects, such as murals.