A careful exposure helps to assure there is detail in the highlights and shadows. It’s easy to know how by checking the percentages in Lightroom or the numbers in Photoshop. Here’s how to know. It’s easy.
Detail by the numbers
The numbers or pixel brightness values must be understood to get a grasp on clipping. Fortunately, they are not difficult to understand. In Lightroom, black is represented by 0% and white is known as 100%. (Yes, I know that means there are 101 possible percents. Seriously, black is always zero. And white just would seem white at 99 now would it?)
Highlights with detail
Lightroom highlights will show detail when the percentages are no brighter than 96.1%. 95.1% is safer for detail in making prints. Staying under 96.1% will mean the platinum white hair won’t merge with the snow in the background. (Highlights with detail in Camera Raw are between 242 and 249). If they are too bright, use the Highlights slider in Lightroom or Camera Raw to tone them down.
Tip: Hold down the Option or the Alt key. The screen goes black except for the highlights that are blown out. Move the Highlights slider to the left until they turn black.
Shadows with detail
The darker side of Lightroom wants at least 7% as the threshold for shadow detail. Under that, they block up. A properly exposed photograph will most times show a lot more shadow detail than 7%. It’s common for that number to be as high as the 40s (Camera Raw shadows block up below 25). Shadows may be opened up to show more detail with the Shadows slider in both applications. The tip above works too. The screen will turn white with black or colors. Move the Shadows slider to the right until only the areas you want to be black show.