HOW TO CAPTURE THE BEST EXPOSURE
After gaining an understanding of Metering and Exposure modes, discussed in Lesson 1 (of 5) of this blog, it’s time to put this knowledge to use. Bald eagles can be a challenging subject for many reasons as I had outlined in the previous lesson. Let’s face it, any type of action photography is a game of chance and this subject adds a few unique challenges. If the goal is to increase the number of “keepers”, the following tips and tricks should help you maximize your results.
TIP #1 – ESTABLISH A BASELINE EXPOSURE
In order to establish a baseline exposure for this example, we need start by making two assumptions. First, cloudy skies have tendency to be wildly inconsistent when it comes to the quantity of light that they provide. For this example, we need to assume that the sky is relatively clear of clouds. Second, we have to assume that you have positioned yourself in such a way that the light (sun) is falling on the subject at the correct angle as metering a backlit subject is fluid.
STEP 1: Start by ensuring that your White Balance, Exposure Mode and ISO are set to Manual.
STEP 2: Set your camera’s White Balance to Sunlight.
STEP 3: Set your camera’s ISO to 400.
STEP 4: Set your camera’s shutter speed at 1/3,200th of a second.
STEP 5: Set your camera’s aperture at f7.1.
Assuming the sunlight is strong and not diffused by clouds or the horizon, these settings can be used in the vast majority of occasions. Unless the light changes, there is no need to modify them. A shutter speed of 1/3,200th is fast enough to stop most action when it comes to bald eagles. Stopping down to f7.1 will give you a bit of leeway in terms of depth of field which is at a premium with large telephoto or zoom lenses.
Again, this is the start of establishing a baseline exposure where you are controlling the metering instead of relying on the camera’s technology. While light temperature, quantity and quality can very greatly, this baseline has been used for the vast majority of my work over the past decade. Simple adjustments can be made to maximize your results down the road and I recommend testing your exposure frequently by taking a close look at the eagle’s head with your camera’s LCD screen. If it’s blown out, close the aperture down to f8.0 or f9.0 and take another test shot.
TIP #2 – SEAGULLS HAVE A PURPOSE AFTER ALL
You’ve successfully established your camera’s exposure and but it’s been a few minutes. You’re not sure if the light is as intense as it was and want to double-check. Rather than wait until the next frenzy or action sequence and miss out on a the potential of a wall-worthy photo, try testing your camera’s settings on something that is similar to the bald eagle’s head.
Thankfully, there doesn’t appear to be a shortage of seagulls in the world and those pesky critters are absolutely perfect for conducting a test exposure. Take a test shot and examine your settings by using your LCD screen to zoom in on the subject. Similar to the process of establishing a baseline exposure (Tip #1), if the feathers lack detail, stop down. If they appear too dark, open your aperture (example: f8.0 becomes f7.1) until you get the desired exposure.
While adjusting the aperture is my first choice when it comes to making adjustments, ISO is typically the next best solution. As the sun approaches the horizon, light quantity will begin to diminish, forcing you to make decisions on which part of the exposure triangle to sacrifice. If you ask 10 photographers what they prioritize, you will likely get 10 different responses. Some will reduce shutter speed. Some will increase ISO. Just remember, each component of the exposure triangle impacts the other. Use your down time wisely by continuously checking your exposure with test shots.
A few things to consider:
- Lower shutter speeds can result in more motion blur. As a general rule for stopping action, keep the shutter speed at 1/1,000th or higher.
- Higher ISO leads to more noise. There are some assumptions in this statement as an underexposed image at 640 ISO will have more noise than a well exposed image at 1,600 ISO. The useful maximum ISO is different for each camera but staying below 3200 is a good start.
- Wider apertures lead to more bokeh. Shooting at f4.0 vs f8.0 will help your subject “pop” from the background by increasing focus differentiation.
- Wider apertures lead to less room for error. Shooting at f8.0 vs f4.0 gives you a bit more leeway for making mistakes as depth of field is slightly increased.
- Can’t find a seagull? Almost anything white will work. The best subjects for test shots generally have dark detail that allow you to distinguish a point of differentiation.
TIP #3 – USING YOUR HISTOGRAM
The trusty screen on the back of our cameras can be an extremely useful tool for a lot of things. Having the ability to view our images and check our focus and exposure by simply looking at the photo is the most notable. But what if the brightness settings of your LCD screen are out of whack? Thankfully, today’s histograms allow us to see a graphical representation of our exposure that isn’t biased by screen settings.
Interpreting this data can seem like a tall task at first. However, diluting this information down for the use of bald eagle photography is relatively simple. After all, a proper exposure of the eagle’s white head is our main concern and outweighs everything else in the frame.
Before diving into the graph, take a look at this image and notice the tonal values across the frame. Lot’s of midtones in the background, near black from the eagle’s wings, and a small amount of white due to the bird’s head and tail features.
When you look at this photo represented in graphical form, you’ll notice exactly what we saw when looking at the photo itself. Strong midtones which are represented in the center, another spike in on the left side which signifies that the pixels are close to black, and a small amount of white in the frame.
If we follow this process for another image, notice the dark tonal values throughout the frame. Sure enough, the histogram favors the left side with a small amount of information to the right.
When considering the other end of the spectrum, based on the large amount of white in this image, the histogram should be the converse of the previous, with most of the data favoring the right side.
Now let’s take a look at an image that was overexposed (according to the camera’s light meter). Notice how the spike in data on the right side of the graph is touching the edge? That means that the image contains a significant amount of true white. In other words, white without detail. You’ll also notice that the head contains detail and appears slightly darker in the image than the snow in the background. Very close to white, but the detail in the head was preserved.
This is how you use your histogram for checking exposure. If the graph has a significant amount of data touching the left of the graph, you have captured a large amount of true black in the image. If you have a significant amount of true white, the spike in data will touch the right side. There will be times that this is intentional, like when there is a large amount of snow in the scene. However, if the snow is vastly overexposed, the eagle’s white head may also be overexposed. Remember, we are looking to capture detail in the head.
For a great video covering the basics of using your histogram visit Tony and Chelsea Northrup’s YouTube channel: https://youtu.be/ZmAw_Zd7zP4
TIP #4: THE THREE CLICK RULE
If every bald eagle sported the white head, metering would be easy. But what about juveniles? If your camera settings are left unchanged as if you were photographing the white head of a mature bird, every image that you capture of a juvenile will be underexposed, making them appear very dark in the final result.
While light intensity may vary drastically throughout a given day, one trick has proven useful for many years. When you have identified a juvenile and need to make a quick adjustment in the camera’s exposure, simply follow the Three Click Rule by opening up your aperture by one full stop (three clicks). In other words, if you are using the baseline discussed previously, your shutter speed was set to 1/3200 with an aperture of f7.1. After following this rule, your aperture will be f5.0, shutter speed will remain at 1/3200.
Does this sacrifice depth of field? Yes. But it’s better to capture the correct exposure and gamble on your focusing technique than to take a photo that you’ll simply delete in a few hours due to the incorrect exposure.
TIP #5 – AUTO EXPOSURE COMPENSATION
If you’re not ready to tackle manually exposing your images, there are a few things you can do to increase the likelihood of a good exposure in Program, Shutter Priority, or Aperture Priority modes. This still puts most of the trust in the camera’s meter and increases the impact of any sort of change in the light source, but it’s far better than allowing your camera to make 100% of the decision.
Auto Exposure Compensation is a feature that allows you to make adjustments to the exposure settings that the camera provides. Make no mistake, this is not ignoring the camera’s meter. You will simply take the camera’s suggestion and tell it to override them by a small amount.
Find the Auto Exposure Compensation button on your camera by locating the +/- symbol. This is usually on the top of the camera. On a sunny day, start by underexposing by 1.7 stops (-1.7). If you are shooting on a cloudy day, start by underexposing by 0.7 stops (-0.7). Notice the word “start” in both of those sentences. As with Manual Exposure Mode, you will need to take a few test shots to ensure the settings are in line with the light source.
Its important to keep in mind that this method has it’s limitations. If the bird flies in front of a snowy background, the camera will assume that there is a ton of light, automatically adjusting the exposure accordingly. If the subject flies in front of a dark background, the camera will assume it needs to let more light hit the sensor for the proper exposure. Limitations aside, fine tuning exposure is far better than putting 100% faith in your camera’s metering technology.
TIP #6 – ADJUSTING WHITE BALANCE
By now you should assume that I am going to suggest that you use the camera’s manual setting when it comes to white balance. You would be correct. However, there are exceptions.
Getting your white balance settings wrong can result in a turquois sky during a sunny day and far, far too much blue on a cloudy day. Correcting color temperature during post processing is one of the easiest things to correct. However, for those of us who would rather sit behind our camera instead of in front of our computer, we like to get it right the first time.
Manually adjusting white balance is the preferred method on most circumstances, but weather can make the automatic settings an attractive option. If you find that you are having to spend too much of your attention constantly changing your white balance settings due to scattered clouds or other changes, take advantage of the automatic setting. While the camera will make the wrong call on occasion, a few minutes of editing in post is far better than missing the shot altogether.
This excerpt was taken from my latest project, a book titled Bald Eagle Photography – A Photographer’s Guide, which is scheduled to be published in later in 2019. To add your name to the mailing list for updates on its release, let us know who you are: https://ajharrisonphotography.com/book-release-update-request/