The Definitive Guide to Museum and Art Gallery Lighting: Balancing Conservation, Aesthetics, and Visitor Experience

Imagine standing before a masterpiece. In one gallery, the colors leap from the canvas, every brushstroke telling its story under a soft, focused glow. The air hums with reverence. In another, the same painting sits under harsh, flat light, its vibrant hues muted, its texture lost. The magic is gone. This is the power of museum lighting. It is more than just illumination; it is a delicate, scientific art form. It’s the critical balance between creating an unforgettable visitor experience and fulfilling the profound duty of preserving our shared cultural heritage for generations to come.

This essential role, however, is built on a fundamental conflict. Light is the very medium that allows us to see and appreciate these treasures, but it is also a silent destroyer, a primary cause of irreversible damage. How do we navigate this paradox? This guide is your map. We will explore the science behind light, help you choose the right technology, design a masterful lighting plan, and master the principles of conservation. Let’s illuminate the path to a perfectly lit—and perfectly preserved—collection.

Part 1: The Foundations – Why is Museum Lighting So Important?

Proper museum lighting achieves two monumental goals at once: it captivates the public while safeguarding the priceless artifacts on display. It’s an invisible curator that shapes perception, emotion, and even the physical integrity of our history. Understanding its dual role is the first step toward a successful lighting design.

1.1 How Does Lighting Shape the Visitor Experience?

The moment a visitor steps into a gallery, their experience is being sculpted by light. It’s a powerful tool that transforms a simple viewing into a memorable journey.

• Enhancing Visual Perception: Great lighting is what makes art come alive. It allows the human eye to perceive the full spectrum of colors the artist intended, revealing the subtle shifts in tone and the intricate textures of the medium. Think of the delicate weave of an ancient textile or the bold, impasto brushstrokes on an oil painting. Without the right light, these crucial details are lost, and the artwork is not truly seen.
• Creating Atmosphere and Mood: Lighting is the architect of atmosphere. Do you want a dramatic, focused space where a single sculpture commands all attention? Or a warm, inviting gallery that encourages visitors to linger and explore? The warmth, direction, and intensity of light create an ambiance that can evoke feelings of awe, intimacy, or intellectual curiosity, deepening the visitor’s emotional connection to the exhibit.
• Guiding the Narrative: Every exhibition tells a story, and lighting is its narrator. By using the interplay of light and shadow—a technique artists call chiaroscuro—a lighting designer can create a visual hierarchy. Bright, focused light draws the eye to key pieces, establishing focal points and guiding visitors through the intended narrative path of the exhibition. It tells you where to look and what matters most.
• Ensuring Safety and Navigation: Beyond the art, lighting serves a fundamental practical purpose. Proper illumination in entrances, hallways, and staircases ensures visitor safety and easy navigation. A well-lit entrance doesn’t just prevent accidents; it creates a sense of welcome and excitement, setting a positive tone for the entire visit.

1.2 Why is Lighting a Critical Factor in Artifact Conservation?

The same light that allows us to see art is also its most persistent threat. This is the conservator’s dilemma, and understanding the science behind it is non-negotiable.

Light damage is a one-way street. It is cumulative, irreversible, and relentless. Our job is to slow that journey down to a crawl.

• The Science of Light Damage (Photochemical Degradation): Light is energy. When this energy, particularly from invisible Ultraviolet (UV) radiation, strikes an artifact, it can trigger chemical reactions within the material’s molecules. This process, known as photochemical degradation, is just a scientific way of saying that light literally breaks down the object over time.
• Types of Damage: This degradation manifests in several ways. You might see the vibrant colors of a manuscript fade into pale ghosts of their former selves. The paper itself might become yellow and brittle, or the threads of a historic gown may weaken and break. This damage isn’t just cosmetic; it’s a fundamental loss of the object’s physical integrity.
• Cumulative and Irreversible Nature: The most crucial concept to grasp is that this damage is both cumulative et irreversible. Each moment of light exposure adds to the total “dose” of damage an object receives over its lifetime. It’s like a light budget; once it’s spent, it’s gone forever. You can never restore the color that has faded. The conservator’s goal, therefore, is to manage this budget with extreme care, ensuring the artifact can be safely viewed for centuries, not just decades.

Part 2: The Science of Light – What are the Key Metrics for Museum Lighting?

To control light, you first have to measure it. Choosing the right light source isn’t a matter of guesswork; it’s a science based on specific, quantifiable metrics. Understanding these key terms will empower you to select lighting that is both beautiful and safe for your collection.

2.1 What is Color Rendering Index (CRI) and Why is it Crucial?

The Color Rendering Index, or CRI, is a score from 0 to 100 that tells you how accurately a light source reveals the true colors of an object. The benchmark is natural daylight, which has a perfect CRI of 100.

For a museum, CRI is everything. An artist chooses their palette with incredible care, and a low-CRI light source can completely distort their vision, making a vibrant red appear dull or a subtle blue look gray. It’s the difference between seeing a masterpiece as the artist intended and seeing a washed-out imitation.

The Importance of R9: The Red Test

Within the broader CRI measurement, there is a specific value called R9, which measures how well a light renders a saturated red color. This has become an essential ‘acid test’ for modern LED lights, as many standard LEDs struggle to show reds accurately. Since red tones are vital for rendering everything from human skin and rich wood grains to countless historical pigments, a high R9 value is critical for high-fidelity lighting.

Museum Standard for Light Quality: For any serious museum or gallery application, the lighting should meet these minimums:

• Good Quality: CRI ≥ 90 and R9 ≥ 50
• Excellent Quality: CRI ≥ 90 and R9 ≥ 90

Always ask for both CRI and R9 data from a manufacturer. If they can’t provide it, the light is likely not suitable for your collection.

2.2 What is Color Temperature (CCT) and How Do You Choose the Right One?

Correlated Color Temperature (CCT) describes the “warmth” or “coolness” of a white light source and is measured in units of Kelvin (K). It’s a bit counterintuitive: a lower Kelvin value means a warmer, more yellowish light, while a higher value means a cooler, more bluish light.

The Warm vs. Cool Debate

• Warm Light (2700K – 3500K): This range evokes the feeling of candlelight or traditional incandescent bulbs. It creates a cozy, intimate, and often traditional atmosphere, making it a popular choice for historical artifacts, decorative arts, and classic art collections.
• Neutral to Cool Light (3500K – 5000K+): This clearer, whiter light is often used for contemporary art galleries and science museums. It can enhance visual clarity, bring out crisp details, and create a more modern, analytical feel.

While old theories suggested that warm light was always best for the low light levels in museums, recent research shows that visitor preference is more flexible. The most important rule is consistency. Mixing different color temperatures within the same space can be visually jarring, as our eyes need time to adapt. A CCT of around 3000K remains a safe and pleasant all-purpose choice for many museums.

2.3 How is Brightness Measured (Lumens & Lux) and What are the Recommended Levels?

It’s easy to confuse Lumens and Lux, but the distinction is vital for conservation.

• Lumens (lm): This measures the total amount of visible light produced by a bulb or fixture at the source. Think of it as the raw “power” of the light.
• Lux (lx): This measures the amount of light that actually falls on a surface. This is the number that matters for conservation because it tells you how much light an artifact is receiving. (One foot-candle, an older imperial unit, is approximately 11 lux).

The Conservation Standard: Maximum Light Levels

Based on decades of research, the conservation community has established strict guidelines for the maximum amount of light different materials can safely tolerate. Adhering to these levels is the most important step in preventing light damage.

For general areas like corridors and lobbies where no sensitive objects are displayed, lighting levels can be higher, typically between 100-200 lux for comfortable navigation.

2.4 Why are UV and IR Radiation So Dangerous?

• Ultraviolet (UV) Radiation: This is the invisible, high-energy part of the light spectrum that is the single most damaging component for artifacts. It is the primary driver of photochemical degradation. The professional standard is to keep UV levels below 75 microwatts per lumen (μW/lm), but with modern technology like LEDs, a level of near-zero is both achievable and the new ideal.
• Infrared (IR) Radiation: This is simply radiant heat. Traditional bulbs like halogens produce a significant amount of IR, which can literally cook the surface of an artifact. This localized heating causes organic materials like wood, paper, and canvas to dry out, become brittle, and crack over time.

2.5 What is a Beam Angle and How Does it Control Focus?

The beam angle tells you how wide or narrow the cone of light from a fixture is. Mastering beam angles allows you to paint with light, creating focus and drama.

• Narrow Beams (Spotlights: 10°-25°): These create a tight, focused circle of light. They are perfect for accent lighting—making a single sculpture pop, highlighting a specific detail on a larger piece, or creating dramatic pools of light in a darkened room.
• Wide Beams (Floodlights: >30°): These provide broad, even illumination. They are used for general ambient lighting or for “wall washing,” where you want to light an entire wall of paintings uniformly without creating distracting hotspots on each one.

Part 3: Choosing Your Tools – What are the Best Lights and Fixtures for a Museum?

With the science understood, it’s time to choose your tools. The technology of light has evolved dramatically, and today’s museums have access to options that are safer, more efficient, and more versatile than ever before. The clear winner in this evolution is the LED.

3.1 What is the Best Type of Lighting for a Museum? A Detailed Comparison

For decades, museums had to compromise. They could have excellent color rendering with hot, inefficient halogen bulbs, or they could have energy efficiency with poor-quality fluorescent lights. That era of compromise is over.

The verdict is clear: For any new installation or upgrade, LEDs are the undisputed gold standard for museum lighting, outperforming older technologies on every important metric from conservation safety to operational cost.

3.2 Why are LED Lights Now the Gold Standard for Museums?

The transition to LED lighting isn’t just a trend; it’s a revolution that has solved many of the historical challenges of museum illumination.

• Superior Conservation Profile: This is the most important benefit. High-quality LEDs emit virtually no UV radiation et negligible infrared heat. This means you can light objects safely without cooking them or bombarding them with the most damaging wavelengths of light. This eliminates the need for costly and high-maintenance UV filters.
• Efficacité énergétique & Long-Term Cost Savings: LEDs are marvels of efficiency, using up to 75-80% less energy than a halogen bulb to produce the same amount of light. While the initial investment is higher, the savings on electricity bills are substantial. Combined with their long lifespan, the return on investment (ROI) makes them the most financially sound choice in the long run.
• Longevity and Reduced Maintenance: A typical museum-grade LED can last 50,000 hours or more—that’s over a decade of use in a typical gallery. Compare that to a halogen bulb that might last only six months. This drastically reduces the labor costs associated with frequent replacements and, crucially, minimizes the number of times staff must bring ladders and equipment near priceless collections, reducing the risk of accidental damage.
• Unmatched Versatility and Control: The design possibilities with LEDs are nearly endless. They are available in a vast range of color temperatures, beam angles, and fixture types. Their compact size allows them to be integrated into display cases and tight spaces. Furthermore, they are inherently compatible with modern control systems, allowing for precise dimming and integration into smart, responsive lighting schemes.

3.3 What are the Common Lighting Fixtures Used in Museums and Their Purpose?

Choosing the right bulb is only half the battle. The fixture—the housing that directs the light—is what turns a light source into a design tool.

• Track Lighting: This is the workhorse of the modern gallery for good reason. It consists of a rail (the track) that powers multiple, adjustable fixtures. Its key advantage is flexibility. As exhibitions change, you can easily slide, reposition, and re-aim the lights without any rewiring. This makes it perfect for temporary shows and dynamic spaces.
• Spotlights: These fixtures produce a narrow, controlled beam of light designed for one purpose: to create a focal point. Spotlights are used for accent lighting to make a sculpture feel heroic, to draw a visitor’s eye to a key artifact, or to create high-contrast drama.
• Wall Washers: A wall washer is a specialized fixture that casts a wide, even sheet of light down a vertical surface. Instead of creating “pools” of light on each painting, it illuminates the entire wall uniformly. This is ideal for galleries displaying a series of similarly-sized artworks, creating a clean, cohesive look.
• Recessed Lighting: Also known as downlights or “can lights,” these are installed flush within the ceiling. They offer a sleek, minimalist aesthetic and are most often used for providing general, ambient illumination throughout a gallery space. Some models, called gimbals, are adjustable and can provide a degree of accent lighting.
• Picture Lights: These are small, dedicated fixtures that mount directly onto an artwork’s frame or on the wall just above it. They provide intimate, focused lighting for a single piece and are often used in more traditional or residential-style gallery settings to add a touch of elegance.
• LED Strip Lights: These flexible strips of tiny LEDs have opened up a world of creative possibilities. They are perfect for indirect lighting effects like cove lighting (where they are hidden in a recess to cast a soft glow on the ceiling), for evenly illuminating the inside of display cases without hotspots, or for adding architectural highlights to features like staircases.
• Light Boxes: For artworks that are transparent or translucent, such as photographic slides or stained glass, a lightbox is the ideal solution. It’s a shallow, enclosed fixture that provides even backlighting, making the colors and details of the artwork glow from within.

Part 4: The Master Plan – How Do You Design a Museum Lighting System?

A successful lighting design is born from a thoughtful plan, not a random selection of fixtures. The process starts with research and collaboration and builds layer by layer to create a cohesive, effective, and beautiful environment.

4.1 What is the First Step in Creating a Lighting Plan?

Before you even think about a specific bulb, the first and most critical step is assessment and collaboration. A lighting project that begins with a shopping list is destined to fail. The groundwork involves:

1. Understanding the Collection and Space: Deeply analyze the artifacts that will be displayed. What are they made of? How sensitive are they to light? What are the architectural features of the gallery? Are there historic elements to consider?
2. Collaborating with a Team: Lighting design is not a solo act. It requires open discussion with curators (to understand the narrative goals), conservators (to establish strict safety limits), and exhibition designers (to integrate lighting with the overall layout). My own experience, including insights from projects at institutions like the Fitzwilliam Museum, has shown that this collaborative foundation is the single most important factor for success.
3. Consulting Standards and Guidelines: Familiarize yourself with established professional standards, such as those from the Illuminating Engineering Society (IES), and your own institution’s collections care policy. These documents provide the scientific and ethical framework for your design.

4.2 How Do You Create a Layered Lighting Layout?

Great lighting design rarely comes from a single type of light. Instead, it is built in layers, with each layer serving a distinct purpose. This strategy creates visual depth, interest, and functionality.

• Layer 1: Ambient Lighting (The Foundation): This is the general, overall light that fills the space. Its purpose is to provide a comfortable level of brightness for safe navigation and to reduce harsh shadows. It sets the base mood of the room. This is often achieved with recessed lights, wide-beam track lights, or indirect cove lighting.
• Layer 2: Accent Lighting (The Star): This is the focused, directional light that does the most important job: highlighting the artwork. Accent lights create the focal points that guide the visitor’s eye. The contrast between the brighter accent light on an object and the dimmer ambient light around it is what creates visual excitement and drama. This is the world of spotlights and narrow-beam track lights.
• Layer 3: Decorative Lighting (The Jewelry): Sometimes, the light fixture itself is a work of art. Decorative lighting includes things like chandeliers, sconces, or custom-designed light installations. Their primary purpose is aesthetic, adding a final layer of visual interest and character to the space.

4.3 Should You Use Natural or Artificial Light?

This is a classic debate in museum design. Each source has powerful pros and serious cons.

• Natural Light (Daylight):
  • Avantages: It offers a perfect CRI of 100, rendering colors with absolute fidelity. It also creates a dynamic, pleasant connection to the outside world.
  • Les inconvénients: It is incredibly difficult to control; its intensity and color change throughout the day and with the weather. Most importantly, it is saturated with highly damaging UV radiation.
  • The Verdict: Natural light should be treated with extreme caution. It can be used for general, ambient illumination but must be heavily controlled with UV-filtering films on all windows, as well as blinds, shades, or shutters. Direct sunlight must never, under any circumstances, touch a light-sensitive artifact.
• Artificial Light:
  • Avantages: It is 100% controllable. You can choose the exact intensity, color temperature, and direction you need to meet both aesthetic and conservation goals. It is stable and predictable.
  • Les inconvénients: It can be of poor quality if not selected carefully, leading to bad color rendering or unwanted glare.
  • The Verdict: Artificial light is the primary and most essential tool for responsible exhibition lighting. A well-designed system gives you all the control you need to create a beautiful and safe environment.

4.4 Why is a Flexible Lighting Design Essential for a Modern Museum?

A museum is not a static space. Exhibitions change, collections rotate, and new stories are told. A rigid, fixed lighting system is a liability in this dynamic environment.

A flexible lighting system future-proofs your gallery. It allows you to adapt to any curatorial vision without starting from scratch.

Here are the key tools for achieving flexibility:

• Track Lighting: As mentioned before, this is the ultimate solution for flexibility, allowing fixtures to be moved and re-aimed with ease.
• Lighting Zones: Divide larger galleries into smaller “zones,” each with its own set of lights on independent controls. This allows you to create different lighting scenes in different parts of the room simultaneously.
• Smart Controls: Advanced control systems (like DALI or wireless smart systems) are game-changers. They allow staff to adjust brightness, color temperature, and focus remotely via a tablet or control panel, eliminating the need for ladders and manual adjustments for every small change. This saves time, reduces risk, and offers unparalleled creative control.

Part 5: The Conservator’s Dilemma – How Do You Balance Preservation with Public Access?

Every decision in museum lighting comes back to this central conflict: the need for people to see the collection versus the need to protect it from the very light that makes it visible. This is where policy, science, and practical strategy converge.

5.1 How Does Light Damage Accumulate? The Lux Hour Budget

To manage light damage, we must first understand how it’s measured. The total light exposure an object receives is a product of both intensity and time. This is calculated with a simple but powerful formula:

Exposure (in Lux Hours) = Light Level (in Lux) × Time (in Hours)

Think of it like a “sunburn” for an artifact. A short exposure to very intense light can cause the same amount of damage as a very long exposure to dim light. For example:

• 1 hour in direct sunlight (100,000 Lux) = 100,000 Lux Hours of exposure.
• 2,000 hours in a perfectly lit gallery (50 Lux) = 100,000 Lux Hours of exposure.

This concept gives rise to the idea of a “lifetime light budget” for each artifact. A conservator’s job is to spend this budget as slowly and wisely as possible, ensuring the object lasts for centuries. Every lighting decision—from the lux level to the gallery’s open hours—is a withdrawal from this finite budget.

5.2 What are the Official Standards for Museum Lighting and Exhibition Duration?

To standardize this process, leading institutions and engineering societies have published formal guidelines. These are not just suggestions; they represent the professional consensus on responsible collections care.

• IESNA Standards: The Illuminating Engineering Society of North America (IESNA) publishes key documents like IES RP-30 (“Lighting for Museums and Art Galleries”), which provides comprehensive technical guidance.
• CCI Technical Bulletin 36: The Canadian Conservation Institute’s bulletin on LEDs is a landmark resource, providing evidence-based recommendations on LED selection and damage potential. It is the authority on the transition to modern lighting.
• Institutional Policies: Many major museums publish their own internal guidelines. The standards from the Smithsonian’s Freer Gallery of Art & Arthur M. Sackler Gallery are a benchmark for the entire field.

5.3 What Practical Strategies Can Minimize Light Damage?

Armed with these standards, you can implement a multi-faceted strategy to protect your collection.

• Limit Exposure Time: This is the simplest and most effective strategy. Always turn lights off in galleries when the museum is closed to the public. Every hour of darkness extends the life of an artifact.
• Use Smart Controls: Implement dimmers and motion sensors. This ensures an object is only fully illuminated when a visitor is standing in front of it, dramatically cutting down its total lux-hour exposure over the course of a day.
• Rotate Collections: For any light-sensitive object, a strict rotation schedule is mandatory. After its allotted time on display (e.g., 3 months), the object must be returned to complete darkness in storage to “rest” and halt the accumulation of damage.
• Use Facsimiles for “Un-exhibitable” Items: Some items, like the original copies of founding national documents or extremely fragile manuscripts, are too sensitive for any light exposure. In these cases, a high-quality facsimile (a precise replica) is displayed, while the original remains in a climate-controlled, dark vault.
• Establish a Monitoring Routine: You cannot manage what you do not measure. A robust monitoring program is essential. This includes:
  • Regularly taking spot readings with a luxmètre to ensure light levels are correct.
  • Using dataloggers to track light, temperature, and humidity over time.
  • Placing blue wool standard cards (which fade at a known rate) inside display cases as a visual check on the total light dose.
  • Keeping a permanent record of light exposure for each object in your collections management software.

Part 6: From Theory to Practice – A Step-by-Step Guide to Selecting Museum LEDs

You’ve done the research and made a plan. Now it’s time to choose the actual hardware. Selecting the right LED lamp requires a methodical approach to ensure you get the quality you’ve specified. This checklist, based on best practices from leading conservation science bodies, will guide you through the process.

Phase 1: Pre-Purchase Research and Specification

1. Define Your Needs: Before you shop, know what you’re looking for. For each application, specify the required CCT (e.g., 3000K), beam angle (e.g., 25°), and approximate lumen output needed to achieve your target lux level.
2. Set Strict Quality Criteria: This is your non-negotiable checklist. Your specification sheet sent to suppliers must state: CRI ≥ 90 and R9 ≥ 50 (or R9 ≥ 90 for critical applications). Do not compromise on these numbers.
3. Research Reputable Suppliers: Look for manufacturers with a proven track record of supplying to museums, galleries, and high-end retail. These companies understand the need for quality and can provide the necessary technical data, such as IES LM-79 reports, which certify a lamp’s performance.
4. Demand a Written Warranty: A good warranty is a sign of a confident manufacturer. Ask for a warranty of at least 3-5 years that covers not just catastrophic failure, but also performance metrics like significant lumen depreciation (dimming) and color shift over time.

Phase 2: In-Situ Evaluation of Trial Lamps

Never buy hundreds of lamps based on a spec sheet alone. Real-world testing is essential.

5. Purchase a Few Samples: Order a small number of trial lamps from your top two or three potential suppliers.
6. Test in the Actual Space: Install the lamps in a gallery mock-up or a small section of the actual exhibition space. Live with them for at least a week to check for any overheating or performance issues.
7. Conduct a Thorough Visual Assessment: This is a team effort involving curators, designers, and conservators.
   • • Look at the Artwork: Do the colors look vibrant and accurate? Does the light reveal texture effectively?
     • Look at the Light Beam: Project the light onto a blank white wall. Is the beam edge soft or harsh? Is the color consistent across the beam, or are there yellow or blue fringes?

   - Look at the Fixture: When you walk through the space, does the lamp itself create uncomfortable glare from different viewing angles?

8. Test the Controls: If you plan to use dimmers, test them across the full range. Check for any perceptible flicker or buzzing noises.

Phase 3: The Final Purchase and Installation

8. Analyze the Return on Investment (ROI): Using the energy consumption data from the spec sheet, calculate your long-term savings on electricity and maintenance. This helps justify the upfront investment to stakeholders.
9. Place Your Order: With confidence from your in-situ testing, place the bulk order with the supplier whose product performed the best.
10. Document Everything: Once installed, create a comprehensive record. Note the make, model, specifications, and installation date of the new lamps. This information is invaluable for future lighting audits, maintenance schedules, and updating your institution’s lighting policy.

Conclusion

Museum lighting has undergone a profound transformation. The modern, high-quality LED has solved many of the age-old conflicts between display and preservation. It is now entirely possible to create visually stunning, emotionally resonant exhibitions while upholding the highest standards of conservation safety. We can bathe our collections in beautiful light that is also gentle and protective.

The path to perfect lighting is not one of chance, but of choice. It is a fusion of art and science, requiring collaboration, meticulous planning, and an unwavering commitment to quality. By embracing a methodical, evidence-based approach, you can honor the artist’s original intent, captivate every visitor who walks through your doors, and fulfill your most sacred duty: to ensure our shared cultural treasures survive to inspire and educate for centuries to come.

Frequently Asked Questions (FAQs)

1. What is the best color temperature for an art gallery?

A color temperature (CCT) between 3000K and 3500K is generally recommended as it provides accurate color rendering with a pleasant, slightly warm atmosphere. However, the final choice depends on the specific art being displayed and the desired mood; contemporary art may benefit from a cooler CCT (up to 4000K or 5000K).

2. What CRI is needed for museum lighting?

A minimum Color Rendering Index (CRI) of 90 is the professional standard for museum lighting. For the most critical applications, you should also seek out a high R9 value (for red rendering) of 90 or above to ensure all colors, especially skin tones and earth tones, appear natural and vibrant.

3. Are LED lights bad for artwork?

No, quite the opposite. High-quality, museum-grade LEDs are the safest form of lighting available for artwork. This is because they emit virtually no damaging Ultraviolet (UV) radiation and negligible Infrared (IR) heat. The myth that LEDs are harmful comes from early or low-quality products. Proper selection based on technical specifications is essential.

4. How do you prevent glare on paintings?

To prevent distracting glare and reflections, position your lights so they strike the artwork at a 30 to 45-degree angle. Use lighting fixtures that have good shielding, such as deep baffles, snoots, or honeycomb louvers. Additionally, using a lamp with a frosted or diffused lens can help soften the light and reduce specular reflections.

5. What is the maximum lux level for sensitive artifacts?

For highly light-sensitive materials such as watercolors, historic textiles, manuscripts, and fugitive dyes, the maximum recommended light level is 50 lux. Sticking to this strict limit is one of the most important measures for long-term preservation.