Which is the correct illuminant for my application or product?

 

This depends and may vary from application to application…

 

For example: the industry standard for daylight is D65, but in the printing industry and graphic arts, the daylight standard is D50. In other applications, e.g. in the presentation of materials under fluorescent lamps, daylight might not play the major role but TL84 is the primary illuminant to evaluate your samples with. If you are not sure, please clarify the requirements with your customer or technical department.

 

the most important illuminants used is D65, D50 and A.