Okay – it’s time to continue the discussion on bird photography basics. Well, I might cover some more advanced stuff too, but you get the picture. If this is your first time dropping in on this series, you may need to pour a larger cup of coffee and read the previous episodes first:
The ISO Dilemma
I didn’t touch much on ISO during the previous discussion – focusing more on aperture and shutter speed settings for specific scenarios. If you want a good principle from which to base your ISO selection on, then read THIS POST by Andrew Beck. To quote the man himself: “Your ISO value should be as high as necessary, but as low as possible…”
In general – ISO 400 or 800 is great for birds (especially if you’ll need to crop afterwards) – but most modern cameras can produce great results in the ISO 1000 to 1600 range if you expose correctly. What I can expand on is how I use “auto ISO” on my Nikon cameras. I currently almost always shoot in manual mode, with auto ISO enabled. Usually, when shooting Aperture or Shutter priority, you can use your EV setting (exposure bias/compensation – this is usually the button with the +/- on and is toggled when you press the button and scroll one of the selection wheels left or right) to adjust how the camera will meter for the particular shot/situation you are in. Setting it to +0.3 means you are telling the camera to overexpose by a third of a full stop of light.
If you are shooting in Aperture priority, with a fixed ISO, your camera compensates for this exposure using the variable available to it – shutter speed. It will then choose a slightly slower shutter speed to achieve the +0.3 overexposure. Likewise for underexposing. Now, when shooting like I do in manual mode, where I personally select the aperture and shutter speed I ideally want for the shooting situation I am in, you can still use your EV adjustments if auto-ISO is enabled, and the camera will adjust your exposure by adjusting the ISO setting. This helps me focus on getting the shot, especially in situations with rapidly changing or variable light, while the camera chooses the lowest possible ISO setting for the specific aperture/shutter speed combo I have dialed in. Does it make sense?
Canon used to have an auto ISO function but the cameras didn’t allow you to use your EV compensation to manipulate the exposure using ISO. The latest firmware upgrades for the 1Dx and 5Dmk3 have addressed this issue as far as I know (would love to hear from some people shooting Canon if it’s been sorted out?).
Exposure Control Tips
Let’s stick to the topic of Exposure Bias (EV). It’s a tool you will need to learn to use quite well when photographing birds. Bird plumage is often terribly difficult to expose correctly, especially in birds with highly contrasting plumage colours (like black and white birds, or red and black birds for example). This is compounded by the fact that the camera’s metering can be thrown off (misguided) based on the background against which you are photographing the birds. Knowing how to adjust your overall exposure via your EV dial is critical for nailing the exposure on these kinds of birds. The tips below are based on the assumption that you’re using the matrix or evaluatative metering modes. When you use spot metering, the camera will take a reading from the specific point in the frame that you are focusing on and metering from, where the matrix/evaluatative metering modes ensures that the camera uses a larger area or an aggregate exposure to ensure the image is rightly exposed.
1. Blue Sky/Snow/Bright Backgrounds
Blue Sky is a bugger (I won’t mention snow as I’ve never photographed in snowy environs, but the principle is the same). You’d really think that it’s easy to photograph birds against the blue sky, but you need to bear in mind that the camera will actually underexpose the entire image because of the overall brightness of the sky and the “visual weight” it takes up in the viewfinder compared to the bird. So, in general, for photographing birds against a blue sky I would advise that you dial in a postive EV like +0.3 or +0.7 or even +2 depending on how dark your bird’s plumage is (higher for darker birds).
This African Darter has a very dark plumage, and despite the nice golden light hitting its belly and underwings I had to compensate my exposure to +1.7 (one and two thirds) in order to get the detail I needed. Notice that the sky is not blown out.
2. Neutral Coloured Backgrounds
For neutrally coloured backgrounds like yellow grass or surface water on a pond or lake, it’s usually safe to opt for an EV of zero or +0.3, all other things being equal.
This Giant Kingfisher was photographed with an EV setting of zero – thus an even exposure.
3. Dark Backgrounds
Think dark greens (willow leaves), or shaded areas behind the subject, or dark brown dirt, etc – these backgrounds have the opposite effect of the blue sky and snow in that they cause the camera to overexpose based on the metering of the overall scene. Many of these tips will be “in the range of” – in that you need to go out and practice on the types of birds that frequent your area, and the backgrounds you will be shooting against. I want you to take home the principles here and go and apply them in the field and hone your own understanding of them. For darker backgrounds and in scenes where your bird is considerably lighter than the overall scene you’ll need to think of underexposing your image by anything from -0.3 to -1 to prevent the bird (your main subject after all) from being blown out and robbed of valuable detail as your camera tries to expose for the entire scene.
Cattle Egrets against dark bodies of water or willow leaves is a great example. A great majority of people in the world know and have access to photographing this common bird. This photo was captured using an EV setting of -1 (thus I needed to dial the exposure compensation down to a full stop in order to preserve the detail in the white plumage when shooting against a starkly contrasting dark background).
I’m going to keep this episode short and end it here. I hope this short discussion has given you plenty to think about and practice as you go out this week to your local birding spots. Please feel free to ask me questions in the comments below and I will gladly try to explain things better if something is unclear. I am getting a lot of guidance in terms of what aspects to include in this series merely from the questions you guys are posting.
Until I write to you again – keep those shutters clicking!
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