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Shaping light for video in the age of LEDs : a practical guide to the art and craft of lighting
\"A practical, hands-on guide to lighting for video, this book explores how LEDs are changing the aesthetics of lighting and provides students with an indispensable guide to the everyday techniques required to produce professional quality lighting in the age of LEDs and wireless control options. The book focuses on first-hand application of technical knowledge, beginning with simple lighting setups and progressing to more complicated scenarios, and features accompanying diagrams, illustrations and case studies to demonstrate their real-world application. Key topics covered include basic three-point lighting, lighting moving actors, set lighting and exposure, instrument selection, bringing style to your lighting, color temperature and the Kelvin scale, exterior lighting, lighting categories and genres, green-screen techniques, money and budgeting, and electricity and electrical distribution. The book also provides guidance on career paths including what a grip does, case studies with photos and diagrams, and an extensive glossary of set terminology to introduce students to the language of filmmaking. A must have resource for film and media production students taking classes in lighting and/or cinematography\"-- Provided by publisher.
Book
Virtual Reality for Smart Urban Lighting Design: Review, Applications and Opportunities
More and more cities are evolving into smart cities, increasing their attractiveness, energy efficiency, and users’ satisfaction. Lighting systems play an important role in the evolution process, thanks to their ability to affect city life at night along with people’s mood and behaviour. In this scenario, advanced lighting design methods such as virtual reality (VR) became essential to assess lighting systems from different points of view, especially those linked with the city users’ expectations. Initially, the review highlights a list of objective and subjective parameters to be considered for the lighting design of three main city areas/applications: roads, green areas and buildings. Besides, the state-of-art in using VR for outdoor lighting design is established. Finally, the Unreal game engine is used to analyse the ability of VR to take into account the lighting parameters, not yet investigated in current literature and to highlight the VR potential for augmenting lighting design. The results confirm the benefit of using VR in lighting design, even if further investigations are needed to establish its reliability, especially from the photometrical point of view.
Journal Article
0308 Impact of Customized Lighting on Sleep in Hospitalized Patients
Introduction Inpatient sleep may be disrupted for myriad reasons, including lighting exposure that is typically fixed at constant intensity and spectra. In this study we employed customized lighting that promotes circadian entrainment by exposing patients to blue-augmented lighting during the morning and blue-suppressed lighting evening to improve sleep timing and duration. Methods Two Mount Sinai hospital rooms (with 2 beds each) were outfitted with Eight Mattress sensors that use a combination of movement, breathing, heart rate, and temperature variables to estimate wake and sleep vigilance states in 30-second epochs. One room contained customized lighting between 7 am and 11 pm, while the other room contained standard hospital lighting. The current analysis includes 60 participants (30 in the control room and 30 in the custom lighting room), who were matched for time-of-year hospital admission date. We first analyzed the probability of sleep during any given 30-second epoch across each subject’s admission and compared the distributions of sleep probability across the 24-hour cycle for all subjects in the lighting vs control conditions. We additionally evaluated total nocturnal sleep duration(11 PM – 7 AM) by 1) summating all sleep epochs on nights containing at least 50% valid data and 2) normalizing all measured sleep epochs to all valid sleep/wake outputs (excluding indeterminate epochs). Results The distribution of sleep probability was significantly different in the lighting vs control condition (p < 0.001) with most apparent diversion of the distributions between 9 pm and 9 am. The average raw nocturnal sleep duration was significantly higher in lighting condition (270.0 ± 23 minutes vs 201 ± 23 min in control, p = 0.037), as was the average minutes of sleep per hour of valid recording (36.9 ± 15 minutes vs 28.4 ± 13 in control, p = 0.022). There were no significant differences in the number of nocturnal wake or indeterminate epochs between conditions. Conclusion Custom lighting appears to promote sleep in hospitalized patients, but the interpretation is tempered by absence of full validation of the mattress sensor against polysomnography. Future work will evaluate differences in sleep timing and continuity between conditions. Support (if any) McClung Foundation, R01 AG066870
Journal Article
0313 Implementation Outcomes from a Multi-Component Lighting Intervention in Shiftworkers on a High-Security Submarine Watchfloor
Introduction Shiftwork is prevalent in the military and causes circadian health and performance impairments. Negative consequences may be mitigated through evidence-based lighting solutions that optimize timing, spectrum and intensity of exposure; however, the practical utility of these solutions hinges on their implementation and adoption. Therefore, we examined the implementation effectiveness of a multi-component lighting intervention that had demonstrated efficacy for improving alertness and performance in active duty service members working nightshift schedules on a high-security watchfloor. Methods Participants worked 12-h shifts (0530-1730) (N=56, 9 females; mean+SE age=28.95 + 0.76). Lighting interventions included two types of LED panels (3,721 cm2) that were either enhanced (SW+) or depleted (SW-) in short wavelength energy (both ~3000 K, ~300 lux at 46 cm from eyes). For both SW+ and SW- conditions, a bank of panels were arranged across the front of the watchfloor and illuminated the entire nightshift. In addition, blue-blocker glasses were worn after nightshifts up until bedtime, and eye masks were worn during sleep for both intervention conditions. Data collection coincided with existing watchfloor schedules: there was an 8-day baseline (BL1) and 8-day SW+ condition, and an 8-day baseline (BL2) and 8-day SW- condition (order within those 16-day periods was pseudo-randomized). Implementation was measured via weekly questionnaires. Results Participants who completed BL1, SW+, and SW- conditions (n =24) reported more positive feelings (happy, alert, relaxed) and fewer negative feelings (sad, sleepy, anxious) with both interventions compared to standard lights (BL1) (p< 0.05 for both SW+ and SW-). More negative symptoms (e.g. glare, headache, fatigue) were reported in BL1 versus the intervention conditions (p< 0.01). Most participants reported that alertness was the same or better under intervention conditions (96% SW+, 95% SW-); 75% found both the blue-blocker glasses and eye masks somewhat or very easy to use; and 100% reported sleep as either the same or better with each intervention tool. Finally, most participants reported they would want to keep the intervention lights at the end of the study. Conclusion The intervention was generally well-received by participants, thus providing evidence for the feasibility of implementing multi-component lighting strategies to mitigate the negative consequences of shiftwork. Support (if any) ONR TS-788
Journal Article
Merging Visible Light Communications and Smart Lighting: A Prototype with Integrated Dimming for Energy-Efficient Indoor Environments and Beyond
This article proposes an improved Visible Light Communication (VLC) solution that, besides the indoor lighting and data transfer, offers an energy-efficient alternative for modern workspaces. Unlike Light-Fidelity (LiFi), designed for high-speed data communication, VLC primarily targets applications where fast data rates are not essential. The developed prototype ensures reliable communication under variable lighting conditions, addressing low-speed requirements such as test bench monitoring, occupancy detection, remote commands, logging or access control. Although the tested data rate was limited to 100 kb/s with a Bit Error Rate (BER) below 10−7, the key innovation is the light dimming dynamic adaptation. Therefore, the system self-adjusts the LED duty cycle between 10% and 90%, based on natural or artificial ambient light, to maintain a minimum illuminance of 300 lx at the workspace level. Additionally, this work includes a scalability analysis through simulations conducted in an office scenario with up to six users. The results show that the system can adjust the lighting level and maintain the connectivity according to users’ presence, significantly reducing energy consumption without compromising visual comfort or communication performance. With this light intensity regulation algorithm, the proposed solution demonstrates real potential for implementation in smart indoor environments focused on sustainability and connectivity.
Journal Article
Bright environmental light improves the sleepiness of nightshift ICU nurses
Background
Shift work can disturb circadian homeostasis and result in fatigue, excessive sleepiness, and reduced quality of life. Light therapy has been shown to impart positive effects in night shift workers. We sought to determine whether or not prolonged exposure to bright light during a night shift reduces sleepiness and enhances psychomotor performance among ICU nurses.
Methods
This is a single-center randomized, crossover clinical trial at a surgical trauma ICU. ICU nurses working a night shift were exposed to a 10-h period of high illuminance (1500–2000 lx) white light compared to standard ambient fluorescent lighting of the hospital. They then completed the Stanford Sleepiness Scale and the Psychomotor Vigilance Test. The primary and secondary endpoints were analyzed using the paired
t
test. A
p
value <0.05 was considered significant.
Results
A total of 43 matched pairs completed both lighting exposures and were analyzed. When exposed to high illuminance lighting subjects experienced reduced sleepiness scores on the Stanford Sleepiness Scale than when exposed to standard hospital lighting: mean (sem) 2.6 (0.2) vs. 3.0 (0.2),
p
= 0.03. However, they committed more psychomotor errors: 2.3 (0.2) vs. 1.7 (0.2),
p
= 0.03.
Conclusions
A bright lighting environment for ICU nurses working the night shift reduces sleepiness but increases the number of psychomotor errors.
Trial registration
ClinicalTrials.gov,
NCT03331822
. Retrospectively registered on 6 November 2017.
Journal Article