fill flash -setting compensation amount

Lifting shadow areas can often bring out strong color casts unless corrected region by region.

Hmmm. I'm wondering if the colour cast(s) seen in shadow areas aren't entirely natural. For example: It's well known that shaded areas in direct sunlight will have a blue cast from blue sky-light, and shaded areas under trees will have a green cast from the foliage.

It's just that their low brightness makes the cast less noticeable, but once you raise that brightness....?

Hmmm. I'm wondering if the colour cast(s) seen in shadow areas aren't entirely natural. For example: It's well known that shaded areas in direct sunlight will have a blue cast from blue sky-light, and shaded areas under trees will have a green cast from the foliage.

It's just that their low brightness makes the cast less noticeable, but once you raise that brightness....?

This is the case, but by brightening the shadow areas e.g. of portraits taken on grass or trees, the green cast becomes very obvious and not like a human observer would see on site. Thus this approach of replacing fill light with mere shadow adjustment in post-processing can lead to quite a lot of work on every image to make the images look natural and "correct" to the human observer viewing the images especially in print. Portrait photographers do a lot of this, but when doing e.g. event photography, there can be a lot of images that need to be corrected to maintain high standards. With appropriately used fill flash, images can be used with minimal post work, and the colour cast is far less objectionable, though this does depend on the ambient lighting conditions (daylight, sunset etc.) and how the colour of the flash blends in the scene, but still I find not having the fill flash available can lead to a lot more work to get acceptable results. People do use reflectors as an alternative or complement to flash to minimize these issues but this can be difficult without an assistant, and if there is an assistant, there is significant additional cost to the customer. BTW I find the shoot-through white umbrella to produce the most natural lighting that blends with the environment better than softboxes or direct flash (which maintain more the original colour of the light source) as the umbrella spreads the light into the surroundings, and this makes the fill flash "adopt" to the surrounding colour scene.