**5. Conclusions**

As a first conclusion, the changes in quality of lighting produce subjective alterations in the observers. It is preferable to use a light source with a Duv value of zero to enhance and comfortably view colour The visual functions affected are accommodation, binocular vision and the quality of the eye, as well as artificial changes in the eye with variations of the pupil or age conditions. Any subjective evaluation procedure for a work of art can be affected by lighting and the living eye.

**Funding:** This was funded by Ministerio de Ciencia e innovacion of Spain with grant number [RTI2018-097633-A-100] And The APC was funded by the project Restauración fotónica aplicada a patrimonio cultura: aplicación al cuadro de dali "dos figuras".

**Conflicts of Interest:** The authors declare no conflict of interest.
