Camera operation: two different exposure methods
Learning to operate the camera and to change settings in an instant, depending on the lighting conditions, the bird’s color, the brightness of the bird’s surroundings and background, and whether the bird is moving, is crucial to improving your skill level in bird photography. Your camera may have “autoexposure” but you won’t be very successful if you let it control your camera. It is not that smart! You must take control and get to where you can change many different settings on the camera without even looking at the buttons. Settings such as focus, ISO, aperture, shutter speed, exposure comp, and sometimes AF area mode. You get to this point through practice–repeated instances of assessing each scene’s situation, day after day, month after month, year after year. As you take more and more bird pictures the more comfortable you will get with your camera. It’s kind of like a cell phone that you use every day. After a while, all the buttons and settings become second nature.
In my eight years of bird photography, I’ve tried two different methods of camera exposure operation. 1) The exposure compensation method in AV (aperture priority) mode with autoexposure on and, 2) the manual mode method where autoexposure is turned off.
1) Av Mode – Exposure Comp
Av mode is Aperture Priority mode. When the mode dial is set to this mode, you then select the ISO and the aperture before taking a shot, and the camera selects whatever shutter speed is necessary to expose the image properly (well, sometimes it’s the proper exposure!). This is a mode where you are letting the camera make the decision of what shutter speed to use. In the process of pressing the shutter button all the way down, the camera reads the brightness factors of the scene and selects the shutter speed depending on how you have set your metering mode. This automatic metering is called the autoexposure (AE) function of your camera.
The autoexposure function will respond a little differently depending on which metering mode you have selected on your camera. Check your camera manual for metering mode and you’ll see it has some or all of these four modes: 1) evaluative metering, 2) partial metering, 3) spot metering, 4) center-weighted average metering. Personally, I use spot metering because I want the camera to consider the smallest area possible since birds can be very small, especially their eyes and heads. If your camera doesn’t have spot metering, then I recommend setting it to partial metering.
Setting the metering mode is good but there is more to consider when getting the right exposure in the camera’s Av mode. In bird photography, you also have the color and brightness of the bird to consider, plus you have the color and brightness of surrounding areas like the sky and water. The camera is going to expose for the brightest thing in the scene, whether it’s the bird, the sky, nearby flowers, etc. This may result in beautiful flowers but an underexposed bird, if the bird is a dark color. If the bird is white, then it may be overexposed because the surrounding area is much darker and the camera tries to bring up the light in that large dark area of the image.
To remedy this photographic challenge, there is a function on your DSLR called exposure compensation (EC). The EC control is typically on a wheel or a dial on your camera and should be very easy to reach and manipulate because it is a very popular feature for many photographers. Check your owner’s manual to determine which dial on your camera operates EC if you haven’t used it yet.
The idea behind EC is to give the photographer control over the camera’s programming for exposure. Sometimes you may need to intervene and override the camera’s choices to get the exposure you want. If your bird is a Great Egret for instance (a completely white bird), you need to be very careful that you do not overexpose (blow out) the white feathers. If you do, there will be no feather detail.
Depending on your model of camera, the EC control can allow you up to 5 f-stops above and below normal exposure. (But your camera will likely only display the setting up to +/- 3 stops in the viewfinder and the LCD panel). So your mission as a bird photographer is to get to know the EC control so well that you can make your camera expose every shot just the way you want it to (yeah, sure). When you’re looking at your bird and the scene, you must determine based on the color of the bird and its surroundings how much your autoexposure function will over or under expose the shot. Then you need to quickly compensate for that by changing your EC and taking your shot.
The EC is usually changed by a dial or a wheel on the camera. You’ll notice that when you turn the dial, it clicks as you turn it–it’s not a free turning smooth motion. On my 7D and my 5D Mark III, by default, each click (increment) is 1/3 of an f-stop of compensation; so I have to turn the dial 3 clicks to adjust the compensation up or down by 1 stop. This means when you turn it that you can turn the dial without looking at it and mentally count the clicks as you turn. If you know the EC was set to zero before you adjusted it, then six clicks to the right will get you to +2 compensation (based on the camera setting of 1/3 per click). Most camera bodies give you the choice of making a wheel click equal to 1/3 stop or ½ stop. If you change it to ½ stop, then, of course, you turn it only two clicks to adjust EC by 1 stop.
The digital age brings us photographers a great thing, and that is the ability to look at our shots on the LCD screen right after you take the shot. I’m not suggesting that you review every shot out in the field but if you see that your first shot of a particular bird is not exposed right, and if the bird is still there on the perch (ha ha!), then you can make an EC adjustment and try again. So when you’re out shooting in Av mode, you need to keep an eye on your EC setting at all times. If you’ve pushed it up 2 stops, say, on your previous shot and you don’t take another shot for a while, it’s easy to forget it’s set at +2. Your next shot could be way over exposed if you don’t happen to look at the settings before you shoot again. Practice is the best way to get to know how your camera acts in different situations.
2) Camera Manual Mode
Around 2010, I started experimenting with Manual camera mode where I place the mode dial on M (instead of Av). I have not looked back and continue to use this method for exposure. This is the second method I talk about for exposing bird shots. Shutter speed, ISO, and aperture are all controlled by me. Autoexposure is turned off automatically in M mode so the camera does not try to guess any settings. I/you (the photographer) still have to “guess” or make a few test shots to determine if the exposure is set right for a particular shot—bird on the ground vs. bird in flight, for instance. But the longer I shoot manually, the better I have become at knowing what the settings should be based on the light available and what kind of shot I’m taking (action vs. stationary). This goes back to my practice, practice, practice mantra. It really does help.
When you think about it, shooting in Av mode and utilizing the EC dial means you’re also ‘guessing’ on exposure there as well. I’m not using the term ‘guess’ here to mean a wild guess but more of an educated guess based on experience. So both methods have some level of uncertainty to them which becomes less and less of a guess as the photographer gets more practice.
One of the best things about shooting manually, especially for bird in flight (BIF) shots, is that it doesn’t matter whether the background changes from light to dark as you are following the bird in the viewfinder (panning). Whatever subject/object you set the exposure for will be exposed correctly no matter where you point the camera. This is not the case when you use autoexposure. Bright or dark areas in the scene can fool autoexposure. I talked about this above in the Av mode section and will discuss it even more in the upcoming bird in flight section.
Getting back to Manual mode! I need to set ISO, aperture and shutter speed in this mode. Each is independent of the other and the camera will not attempt corrections if my settings are way out of whack—except that it will give me a terrible image!
When I started a day of shooting with my ‘old’ 400mm f5.6L, I looked outside and noticed how dark it was. If there was a dark overcast, I knew from experience that my f5.6 lens (set to f5.6) was going to need a higher ISO than my preferred ISO of 400. So I’d kick the ISO up to at least 800 and then see what I could get away with for a shutter speed by taking a quick test shot of a tree or some grass or whatever. If the image was still darker than I liked I had to choose a slower shutter speed, which may well have been as slow as 1/200 or less. With these settings I wouldn’t be taking any great action or bird in flight shots! It’s nice to have at least 1/1000 shutter speed for action shots so I’m nowhere near that. I could bump the shutter speed to 1/250 and use normal sync flash but I’m stuck with taking stationary bird shots—almost any movement is out of the question without motion blur. Later in this series, I go into detail about using external flash so don’t worry if “normal sync flash” doesn’t make any sense to you at this point. I really hoped the clouds would break up or become thinner so there was more brightness from the sun.
UPDATE 29Oct2014: Since I upgraded from the 7D to the 5D Mark III, and also acquired the 500mm f4 lens, I have been successful shooting at ISO 2000 or even higher in certain situations (without flash). The low noise capabilities of the 5DM3 makes it so that I don’t have to slow my shutter speed way down. Instead I now try to keep my shutter speed as fast as 1/1000 in case I come by an action situation, and increase my ISO to what it needs to be. Shooting at high ISO speeds is not necessarily a sure thing though. These shots work better when the bird you are shooting and the surrounding area is a light color. Noise doesn’t show itself in light colors as much as it does dark colors. Also, leaning a little toward overexposure is better than underexposure in high ISO situations. Combining the 5DM3 with the f4 lens has increased my potential shooting flexibility opening up more opportunities for me to get shots. But regardless of the equipment I’m shooting with, the ‘fictitious day of shooting’ described is still relevant and I have the same issues to deal with as far as exposing the shot properly. The main difference now is that I have a new threshold for what ISO I can comfortably shoot at–but the exposure issues and mechanics of resolving them are exactly the same.END OF 29Oct2014 UPDATE.
(Back to shooting with the 400mm f5.6L) As the morning of shooting goes on, I see the clouds are starting to break up and a fairly bright sun is starting to peek through, making lighting conditions much better. So as long as I’m out in open territory where the sun isn’t blocked by trees, I can probably move the ISO back down to my beloved 400, and hopefully push the shutter speed to 1/1600 or 1/2000 (or faster). Now I’m set to capture any shot—action or not. I see there are lots of swans in the lake and I was hoping to get some flight shots of swans landing or taking off. Now is the time that I set my exposure for a white bird so I’ll be ready when the swans fly. I find a seagull flying overhead and take a couple shots of it to test the exposure on white. If I’m able to discern feather detail in the white part of the seagull and if my ‘blinkies’ aren’t blinking (more on this later!), then I probably have a good setting. But in this case I had some blinkies on the seagull in the LCD image and I had to adjust the shutter speed even faster at 1/2500. Now I’m ready to take a shot of a white bird – a swan – no matter what color or brightness is in front of or behind the swan. If a male Northern Harrier flies by I’m in luck, too, because I have my exposure set for white feathers.
So I get a few swan shots and they look good, at least from an exposure standpoint. The light hasn’t changed much and all of a sudden a mature Bald Eagle flies by. This bird has a white head and tail so I have to leave the exposure where it is and hope there is enough ambient light to show detail on the eagle’s dark wing and body feathers. I shoot the eagle at the same settings as I shot the swan (assuming the light hasn’t changed).
Okay, still the same lighting—bright sun peeking through some high clouds. Now a Raven flies fairly close to me and I quickly take some shots of it so I don’t miss it. Ooops! I check the shots on the LCD and see the Raven is just a silhouette of black against the sky. Worthless! My camera was set to expose a white bird! Before I shot and as I was lifting my camera up to my eye, I should have dialed my shutter speed down (using the dial on top of my 7D) probably around 3 or 4 clicks (about 1 stop) to let more light in and to allow the black feathers on the Raven to show some detail. My shutter speed would have ended up being 1/1250, which could still be fast enough to stop the wing action of a large bird like a Raven. I then would have had a fighting chance to get some flight shots of the Raven. I could have also opted to bump up ISO 3 clicks from 400 to 800 instead of changing the shutter speed, giving me better chances of good sharpness but more noise to deal with in post processing. [This all assumes that lighting did not change for the swan, eagle and raven shots. If it had, I would have had to consider the lighting change in my settings].
This fictitious day of shooting demonstrates how important it is to know what your camera is set to at all times. You never know what will appear in front of you at any given moment. And by practicing with whichever exposure method you choose, you can become a good judge of the different exposures required for a black bird, brown bird, or a white bird, and you can apply that judgment quickly so you don’t miss an opportunity.
Now that I’ve covered exposure options, let’s move on to Part 13, and other important camera settings and features that can affect how your pictures turn out.