BirdPhotographers.Net - It Ain't Just Birds

Adapted from "The Art of Bird Photography II" (916 pages, 900 images, on CD only: http://birdsasart.com/ABPII.htm)

Getting the correct exposure with digital capture is a snap once you learn to look at and evaluate a histogram and adjust the exposure for a given subject/lighting combination. But if you miss an opportunity to create a once in a lifetime image while you are still figuring out the best exposure, or if the light changes rapidly and you do not react, you will not be a happy camper.

If one takes some time to study and learn exposure theory, it is easy to come up with near perfect exposures right out of the box without looking at a histogram. With some experience, you will develop your own internal light meter; when the light changes you will find yourself adjusting the exposure almost unconsciously.

After teaching folks how to come up with good exposure settings for more than 20 years, I have simplified things. Here are the basics.

At first, work in Av mode and adjust the exposure suggested by your camera’s evaluative or matrix meter by dialing in plus or minus exposure compensation as needed. Once you have this down pat, you can graduate and learn to work in Manual Mode. It is important to learn to work in Manual Mode if the tonality of the background is changing from moment to moment. If you already feel comfortable working in Manual Mode, simply adjust your shutter speed/aperture settings to reflect the compensations recommended below.

When the sun is out at full strength, that is, on a clear day at least an hour after sunrise or at least an hour before sunset, your camera’s evaluative or matrix meter is smart. It is rare in these conditions that you will need to compensate more than 1/3 stop in either direction. (Note: folks with either Canon or Nikon pro-sumer camera bodies may find it necessary to consistently use more underexposure and less overexposure in a given situation as these meters--on average--tend to overexpose a bit.)

When you are working in the shade, or when it is cloudy or overcast, or when the sun is out at less than full strength, then your camera’s evaluative or matrix meter is dumb. You will usually need to help it out in order to get the exposure that you want. The closer your scene is to white, the more you will need to help the meter.

1: If the sun is out at full strength and what you see in your viewfinder averages to a middle tone or lighter and there are no white or bright highlights, you can use the metered exposure.

(If you are having trouble grasping the concept of averaging a scene to various tonalities, try this: defocus the image completely by turning the manual focusing ring. You should see an out-of-focus swatch of color of a relatively uniform tonality. The color does not matter; what is important is the tonality, how light or dark the color is. Consider blue. A middle-toned blue is the blue of a clear sky about 45 degrees up from the horizon. A dark blue might be the blue of a navy sweatshirt while a light blue would be the very pale blue just above the horizon an hour before sunset on a clear day.

When attempting to judge tonalities accurately, folks are usually way off. Most perceive what is actually a light gray tone as a middle tone. To learn to judge tonalities accurately purchase a cheap grey card and carry it around with you; a gray card is a lot darker than most folks think.( After a while you will become pretty good at judging tonality accurately.)

2: If the sun is out at full strength and what you see in your viewfinder averages to darker than a middle tone and there are no white or bright highlights, you can use the metered exposure less 1/3 stop.

3: If there bright or white highlights in #1 or # 2, use 1/3 stop less light than recommended above.

4: If you are working in the shade, if it is cloudy or overcast, or if the sun is out at less than full strength and what you see in the viewfinder averages to a middle tone, the best exposure will usually be +1/3 stop.

5: If you are working in the shade, if it is cloudy or overcast, or if the sun is out at less than full strength and what you see in the viewfinder averages to lighter than a middle tone, you will need to add light to the metered exposure to come up with a pleasing exposure. The lighter the scene, the more light you need to add.

	a- For scenes a bit lighter than a middle tone, add 2/3 stop of light.
	b- For images well brighter than a middle tone, add 1 full stop of light.
	c- For images that average to white, add 1 1/3 stops or 1 2/3 stops of light.
	d- In white-out, white-sky, or extremely foggy conditions add 2 or more full stops of light.

6: If you are working in the shade, if it is cloudy or overcast, or if the sun is out at less than full strength and what you see in the viewfinder averages to darker than a middle tone and there are no bright or white highlights, you can usually still add a bit of light to the metered exposure. If there are some bright highlights, you can usually get away with using the metered exposure.

It is always best to check your histogram (make sure you have at least some data in the highlights box on the right) and to check for flashing highlights after you have set the best exposure. Most cameras have a flashing highlight alert that indicates you have overexposed some of the lightest toned pixels; you will need to subtract light until no pixels are flashing after you have made an image. Consult your camera body manual for additional details.

Because of the wordy qualifications above, the principles may seem more complex than they really are. To simplify things even further, consider the following:

Situation	Exposure Compensation
Sun out, middle tone or brighter	0
Sun out, image averages darker than a middle tone	-1/3
Sun out, bright highlights	Against middle tone: -1/3 Against dark: -2/3
Sun in, scene averages to a middle tone	+1/3
Sun in; scene averages to lighter than a middle tone	+2/3
Sun in; scene averages to well brighter than a middle tone	+1
Sun in; scene averages to white	+1 1/3
Sun in: white-out or foggy conditions	+2
Sun in, scene averages to darker than a middle-tone	+1/3 or 0 if bright highlights

And remember; it is always best to check your histogram (make sure you have at least some data in the highlights box on the right) and to check for flashing highlights after you have set the best exposure.

In the examples that follow, we shall walk you through the reasoning for each exposure choice. By studying these examples you can quickly learn to apply this rather simple system so that you can consistently come up with a workable exposure in virtually any situation.

Savannah and big sky, Maasai Mara, Kenya. Image copyright: Arthur Morris/BIRDS AS ART

Situation #1- Sun out, middle tone or brighter = 0. Most folks think and most magazine articles tell you that you need to add light with images like this but that would only be true if you were using spot or center-weighted average metering; Evaluative and matrix meters are smart in these situations.

Black Scoter, Cape May, New Jersey. Image copyright: Arthur Morris/BIRDS AS ART

Situation #2- Sun out, image averages darker than a middle tone = -1/3. With a large area of black in the center of the frame (and thus in the center of the metering area), a bit of underexposure is in order. Such situations are rare in nature unless you are photographing large black birds at relatively close range. (Note: though this is a film original, the principles that govern exposure are the same as with digital.)

American Wigeon, drake flapping, Socorro, NM. Image copyright: Arthur Morris/BIRDS AS ART

Situation #3- Sun out, bright highlights against middle tone = -1/3; against dark = -2/3. As soon as we arrive at the wigeon pond, I instruct everyone to dial in -1/3 stop of underexposure for the flapping wigeons and then check for flashing highlights. Once the correct exposure is noted, we advise folks to set it manually.

Pale-mandibled Aricari, Los Bancos, Ecuador. Image copyright: Arthur Morris/BIRDS AS ART

Situation #4- Sun in, scene averages to a middle tone = +1/3. With the bird in the shade, you do not have to worry at all about burning the highlights.

Sandhill Cranes taking flight, Bosque Del Apache NWR, San Antonio, NM. Image copyright: Arthur Morris/BIRDS AS ART

Situation #5a- Sun in; scene averages to lighter than a middle tone = +2/3. In very soft early morning light, +2/3 was perfect here. Thirty minutes later, +1/3 would be perfect; as the sun gets stronger, the meter gets smarter and needs less help from you.

Red-winged Blackbird flock, Bosque Del Apache NWR, San Antonio, NM. Image copyright: Arthur Morris/BIRDS AS ART

Situation #5b- Sun in; scene averages to well brighter than a middle tone = +1. With the soft light and the scene averaging to well brighter than a middle tone, +1 yielded a perfect exposure.

Black-shoulder Kite, Maasai Mara, Kenya. Image copyright: Arthur Morris/BIRDS AS ART

Situation #5c- Sun in; scene averages to white: +1 1/3 or +1 2/3. With a small-in-the-frame subject averaging to lighter than a middle tone and a pure white sky I dialed in +1 2/3 stops of over-exposure and the results were perfect.

Common Raven screaming, Nome, AK. Image copyright: Arthur Morris/BIRDS AS ART

Situation #5d- Sun in: white-out or foggy conditions: +2 or more. On a foggy, foggy day, I metered the sky and added 2 1/3 stops to keep the white sky white and create a silhouetted image of the raven.

Bald Eagle, immature landing, Haines, AK. Image copyright: Arthur Morris/BIRDS AS ART

Situation #6-Sun in, scene averages to darker than a middle-tone = +1/3 or 0 if bright highlights. Here, with a dark subject against a dark middle-toned background, I did not burn the white tail feathers even though I added 1/3 stop of light.