The Vatican has unveiled a high-tech lighting and air-conditioning system to better preserve and display the famous frescoes of the Sistine Chapel.
The new air-conditioning aims to reduce the damage to the frescoes from dust, and from the breath, sweat and heat of some six million annual visitors.
The new LED lighting saves energy and highlights neglected features.
The chapel's renowned sights include a ceiling by Michelangelo, depicting a bearded God giving life to Adam.
The new illumination system comprises 7,000 LED lights.
Some of these lights aim to show off the deep blue background of another Michelangelo fresco, The Last Judgement.
Others highlight frescoes by artists such as Botticelli, Perugino and Domenico Ghirlandaio, whose Sistine Chapel work has been overshadowed by Michelangelo's.
The new lighting is expected to cut the Vatican's energy bills by more than 80%, the Associated Press news agency reports.
The new air-conditioning will move air slowly through the vast chamber, so as not to damage the frescoes.
The flow, humidity and temperature of the air will be adjusted using data from 70 sensors in the chapel walls, as well as from TV cameras that monitor the number of visitors.
Dust, body sweat and carbon dioxide are regarded as major threats to the fragile frescoes.
The existing air-conditioning was installed 20 years ago, when the Sistine Chapel received only 1.5 million visitors every year.
The new systems took three years to install and cost a total of 3m euros (£2.4m; $3.8m), AP reports.
Vatican Museums director Antonio Paolucci told the agency that it was fitting that the 450th anniversary of Michelangelo's death - which falls this year - was being marked by "something durable, not ephemeral".
Michelangelo painted his Sistine Chapel frescoes in the first half of the 16th Century. Their last major restoration, spanning 14 years, was completed in 1994.