News / MacAdam Ellipse

Quality of light that is admired by designers worldwide

Our partner, Xicato, is one of the lighting industries leaders in supplying the lowest tolerances when it comes to MacAdam Ellipse. This is what they have to say.

If we look at the CIE colour space, often used to define and describe white light, we can see a black line running through the centre; this is called the black body locus. As long as the light stays on or about the line, our eyes perceive it as white. If the white light shifts above the line, it will tend to display a green tint; if it shifts below the line, it will display a pink tint. The measurement of visible difference is described as a MacAdam Ellipse.

The measurement of visible difference in colour shift within the CIE colour space is typically described as a MacAdam Ellipse. The smaller the shift along the MacAdam Ellipse, the less noticeable the colour shift will be to the human eye.

Xicato ensures that all of its modules are manufactured to a very tight tolerance for white light, an area that measures 1 step by 2 steps. Most of the industry defines tolerance as within a 3-step area, which is more than three times larger than the Xicato area. When it comes to white light control, some say that Xicato ends where others begin. For more info on how Xicato ensures its module excel in this area visit

Gamma has a range of luminaries which incorporate modules form Xicato:

  • Note – the pinspot downlight range

TTX – part of the powerful Great White downlight range 

LTX – part of the high output track spotlight range