North light (architecture)

[3] In addition, the cool colour of north light has been studied for its effect on our perception of art in galleries and museums.

This is the reason for its diffused nature, as well as why it casts softer shadows than direct sunlight and remains more consistent in colour than light from the east or west (which would be affected by sunrise and sunset respectively).

[6] It first rose to professional importance during the Roman Empire, when architects struggled to improve the ambience of public and religious spaces while reducing glare.

At first, this involved physical structures such as clerestory windows and roof slits, however by the first century CE the direction of light began to play a bigger role.

This makes large north-facing windows better suited for passive houses in warm, tropical climates, as it allows living areas to receive ample sunlight without overheating the building.

[11] Furthermore, accurately depicting harsh light requires a large dynamic range (difference in darkness between blacks and whites) which most traditional paints can not reproduce.

[11] Italian Renaissance painter Leon Battista Alberti alluded to this lack of dynamic range in 1435, writing that “no surface should be made so white that you cannot make it [...] whiter still”.

[12] The use of specifically northern, rather than merely dim light became more common during the Dutch Golden Age with painters such as Rembrandt and Johannes Vermeer.

The use of softboxes and bouncing speedlights against umbrella-shaped diffusers strives to recreate the soft shadows that north light produces.

In addition, dedicated software such as Robin Myers Imaging EquaLight[16] can adjust for lens and lighting falloff, which is especially useful for fine art photographers.

[17] This means that the audience may see art differently to how it was intended and may also miss out on observing subtle changes in shadows and highlights as light moves throughout the day.

[18] A 2008 study by the Optical Society of America used different methodology to suggest 5100K as the optimal temperature[19] – although this is still slightly warmer than natural north light.

Rembrandt's Portrait of Johannes Wtenbogaert (1633) is an example of Rembrandt lighting - diffused light hits the subject from the viewers' left, but some is reflected back onto the subject, creating definition in the subject's face on the viewers' right.
Rembrandt's Portrait of Johannes Wtenbogaert (1633) is an example of Rembrandt lighting - diffused light hits the subject from the viewers' left, but some is reflected back onto the subject, creating definition in the subject's face on the viewers' right.
Direct sunlight casts sharp shadows such as these. As they create dark lines and move during the day, such lighting is often difficult for painters to work with.
Direct sunlight casts sharp shadows such as these. As they create dark lines and move during the day, such lighting is often difficult for painters to work with.