The quality of light is so important in any photographic image… as is the source of the light and how it creates the luminosity of the image.

This cloud image is an interesting example of not quite knowing where the source of light is coming from.

From what I observe in the image, the luminosity of the cloud light is coming from within the cloud, rather than from an external source. I find that really interesting.

In some landscape images, the magic is created when the ground seems luminous, and glowing.. as is often the case in wonderful paintings.

For an interesting exercise, have a look through some of your images and observe the luminosity of them.. and determine the light source and areas which seem to glow or are luminous.