국립박물관 전시조명 환경조사 = An Investigation into Exhibition Lighting Conditions at National Museums

다국어 초록 (Multilingual Abstract)

Conventional types of exhibition lighting at museums include halogen
lighting, optical fiber lighting, and color fading preventive fluorescent lighting.
Strict standards have been applied to the use of lighting at museums. However,
the Minamata Convention on Mercury in 2013 and the Paris Climate Agreement
in 2015 both impacted the use of these existing types of lighting at museums.
Accordingly, more eco-friendly lighting such as light-emitting diodes (LED) has
become popular.
The current regulations for exhibition lighting at museums apply to
fluorescent lights. Thus, in order to use LED lights safely and efficiently, new
exhibition conditions need to be specified by researching and analyzing the
potential impacts of LEDs on cultural properties.
This investigation is part of a three-year survey project conducted from
2017 through 2019 by the National Museum of Korea’s Conservation Science
Division and Well Light, Inc. to examine exhibition lighting conditions at
national museums. It aims to improve the understanding of the characteristics
of LED lights and propose conditions for their use in exhibitions.
To identify characteristics of LED lights in use at national museums, their
correlated color temperature, color fidelity, color fidelity by color, spectral
wavelength, chroma shift by hue, and color gamut were investigated. Moreover,
a survey of LED lights being sold in the market reviewed whether or not they
are suitable for use in museum exhibitions.
The kinds of LED lighting being used at national museums ranged from
concealed panels and angle adjustable spotlights to ceiling concealed and angle
adjustable lights. Most of them had color temperatures of about 3,000 to 4,000
K. LED lights being used at national museums showed wide discrepancies in
average color fidelity with differences of 70 to 90 Rf and color fidelity by color
with differences of 4 to 25 Rf. The color gamut of these lights ranged from
91 to 98 Rg, they showed a low chroma and desaturation, and most of them
had a considerably low range of red (which determines the vividness of color).
LED lights characterized by these features are insufficient to fully express the
original colors of cultural properties.
A survey on LED lights in the market was conducted to examine the
characteristics of respective products. According to the findings, the quality
of some LED lights has been upgraded, and their levels of color fidelity, color
gamut, chroma, and saturation are similar to recommended levels. These
features allow them to fairly express the original colors of cultural properties
containing different materials in exhibitions.
Previously, correlated color temperature and color rendering index have
been taken into account to assess the quality of lighting. As LEDs with varying
spectra develop, however, the precise evaluation of lighting quality is subject
to other considerations, including color fidelity, color gamut, and chroma
shift by hue. For future use of LED lighting for museum exhibitions, color
fidelity, an index used to determine the degree to which an original color can
be reproduced, is recommended to be above 80 for all colors. Moreover, the
recommended color gamut, an index indicating whether color is saturated
or washed out, should fall between 97 and 115. Color fidelity for red, which determines vividness, should be above 95. Similarly, the higher the better for
chroma shift by hue.
If museums select LED lights that satisfy the above-mentioned conditions,
the original colors of cultural properties will be faithfully expressed regardless
of their materials or colors. Displayed objects are influenced by lighting as
well as by the surrounding environment, including the colors of exhibition
spaces, display mounts and veiling reflection. Therefore, if LED lighting and
the surrounding environment are properly applied, the best possible exhibition
lighting allowing cultural properties to display their original colors can be
provided.

목차 (Table of Contents)

• Ⅰ. 머리말
• Ⅱ. 조사 방법
• Ⅲ. 조명 품질 평가를 위한 조건
• Ⅳ. 조명 특징에 따른 문화재 색상 구현 차이
• Ⅴ. 국립박물관에서 사용 중인 LED의 특징
• Ⅵ. 회사별 LED 조명의 특징
• Ⅶ. 조명 구입시 고려해야 할 조건
• Ⅷ. 결론