Thanks for the great information. Perhaps I should have been more clear, but my references for metering pertain more to using artificial lights, such as studio strobes. Obviously when I’m shooting with natural, reflected light only, I meter in the reflected mode, not the incidental mode as reflected metering is more accurate in that type of scenario. Again, thanks for your input and I look forward to your future comments, Rolando.

While I agree about the 90% black/white reflectance you discussed, I kept looking for a way to simply utilize that information… and maybe I am just slow, but I didn’t find it.

In my photography teaching of studio lighting, I tell students to take an incident light leading at the subject position, to get an overall scene exposure. Then take a reflected light reading (using ambient light is fine) off the subjects skin, usually the forehead, and compare that reading to 18% gray. If the reflected light reading is more than 1/3 to 1/2 stop different than 1 stop lighter than 18% gray, the overall scene exposure needs to be modified so that the reflected light reading off the subjects skin is approximately 1 stop lighter than the original scene incident light reading. This provides an exposure which will yield good shadow detail in both the highlights and the shadows, for both caucasian subjects and people of color. The final scene exposure is then the modified incident light reading at the subject position. The final skin tone of the subject can then be decided during the printing process or the computer manipulation of the final image, but you now have sufficient detail in both highlights and shadows to make any corrections you desire.

The background tones are then determined by making an incident light measurement of the background paper or material. Pure black paper will reflect 2 stops less than 18% gray, pure white paper will reflect 2 stops more than 18% gray. For a pure black background, subtract background light (change light angle, flag the key light, or move subject farther away from background) to provide 3 and 1/2 to 4 stops LESS reflectance from the background than the incident light on the subject, keeping in mind that 1 and 1/2 stops less light on the background when added to the 2 stops less reflectance of the black paper will provide the 3 and 1/2 stops less reflectance needed to get a solid black.

Conversely, add enough background light to a white paper background to provide a 3 to 3 and 1/2 stops more reflectance off of the white background, compared to the incident light on the subject. Again, keep in mind that 1 stop more light falling on the white paper background plus the 2 stops more reflectance from the white paper (when compared to the subject) will provide the 3 stops lighter background necessary to have it photograph as pure white. (Note: The background reflectance should never be greater than 3 and 1/2 stops more than the subject, or the white paper can become a light source in itself and create flare in the camera lens, leading to degraded image characteristics which look like a fog over the entire image, but primarily affect the blacks and dark tones.

Of course, for intermediate tones in the background, interpolation of the above can be used to obtain any tone background desired.

I did really enjoy your discussion of the use of white and black V-flats for manipulation of the edge characteristics of the subjects. I often use 4′x6′ V-flats both in both white and crumpled aluminum foil covered versions, as both reflectors and large flags. The use of black V-flats for edge modifications for high key lighting is intriguing and will be tried. My technique of getting a similar effect is to use a large 7′ diameter umbrella directly behind the photographer as the key light (but elevated somewhat, with the center of the umbrella at approximately the photographers head), with no fill light. That does an excellent job of creating the darker edges on the body/figure.

Many thanks to you for your outstanding articles and links!

Don Becker
http://www.donbeckerphoto.com
and
Faculty member and Technical Director
Washington School of Photography
Bethesda, MD 20814
http://www.wsp-photo.com

DSLRs dying is certainly not news. Now, a 12-stop native dynamic range in a compact camera, with razor thing depth of field? THAT would be news!