Bottom line:
Luminance - measured amount of light (only property that can be measured, candelas per square meter)
Brightness - perceived amount of light (from self-luminous things)
Lightness - perceived reflectance of a surface
None of this is relevant unless your comparing it to equal conditions, ie atmosphere, through the same piece of glass (lens) Light is just a disturbance it doesn’t move.
Bottom line:
Getting a human reaction from an image presented in a space where the viewer can gain a sense of emotion could be a great image depending on the viewers level of knowledge of a great image.
Luminance, Brightness and Lightness help focus the viewers attention to a part of the image but the measurement of those properties won’t make an image.
I think the photographer was speaking about his quest to make great images and his journeys that shaped his route.
Good art is emotional to everyone. You don't need a PhD in Art to feel it.
