Exposing for Shadows

[Stud_Pilot]

My photography instructor keeps telling me how important it is to expose for the shadows, and when developing, develop for the highlights. I have a simple question.
Why?
Why do you expose for the shadows, and not the highlights, or middle grey?

 

[Torus34]

For a simple explanation of exposure, development and how it relates to the final print, you might find the following of interest:

http://www.thephotoforum.com/node/47

 

[Digital Matt]

Many scenes that you encounter cover a dynamic range which is wider than the film can capture. You have to sacrifice and lose something. When you shoot with negative film, you can alter your development to bring back highlights, so you should adjust your exposure to get that shadow detail, because it's very difficult to get it back via dev, or printing.

Check out Torus' link, and for further reading, the Ansel Adams series of books are great, and "The Negative" directly pertains to this subject.

 

[Garbz]

It should be noted that quite the opposite is true for digital and slide film. Aside from the resulting noise issues with digital a lot of detail can be recovered from the shadows.

 

[ksmattfish]

Why do you expose for the shadows, and not the highlights, or middle grey?

"Expose for the shadows" doesn't mean meter the shadows, and use those settings. It means be aware of the operation of your equipment, and limitations of your materials and processes, and understand that with neg film details in the shadows are likely to be the first thing you'll lose if you don't do it right.

When you don't have details in the darker sections of a photo, that may mean the neg is transparent there, so there is no way to recover those details. If you block up the highlights, the detail is probably still on the neg, even though it may be a huge pain-in-the-butt to print it correctly. The reasoning behind getting it right in the camera/film processing is that it's a lot easier in the long run to spend extra time getting it right at the point of exposure and processing, rather than spending extra time to fix it everytime you make a print.