Last weeks post on Metering Modes in Wildlife Photography has proven to be very popular which speaks volumes for just how many people out there are unsure of how the various modes work and how they can be used in the field. At the end of the post I mentioned how I prefer to shoot in evaluative metering most of the time, making manual exposure compensation adjustments based on my understanding of how the camera is metering the scene in front of me.
Now I’m going to share a bit more about how manual exposure compensation can be used to save you time in the field and help you get your raw images closer to that ideal exposure that youi had in mind. For the purposes of this post, all examples have been taken using Evaluative (Matrix) metering mode.
The examples shown have also not been edited in any other way and represent the RAW files as imported into Lightroom.
Example 1: Dark Subject Against a Bright Sky
In the previous post I showed how spot metering can be used to lock the exposure of a subject within a scene in order to ensure that the subject rather than the entire scene is correctly exposed. This is great if your subject is static, but what about a bird in flight against a bright sky.
Are you confident that you’d be able to change into Spot Metering Mode and, using only your central focus point, be able to meter correctly off of your subject (assuming you cant link your AF Point to your active focus point)?
Not that easy is it.
In evaluative metering, the camera will be giving you an exposure value based on the entire scene. In this instance the camera would balance out the bright sky and the dark subject resulting in an image which is pretty dark.
Using manual exposure compensation we can dial in an exposure compensation value of +1 which, using the initial metering as a base, will force the camera to brighten (over-expose) the scene by one full stop.
Whilst the sky may not be as dark and may even be leaning towards being over-exposed, I am not phased by this as the exposure of my subject is much better with detail in the shadows and even the mid-tones being presented in a much more appealing way than the cameras initial evaluation.
Example 2: Shooting with a Wide Angle Lens
Shooting with a wide angle lens, whilst including more of a scene, often results in the camera having to deal with a greater range of light intensities across a scene. Even with a very cloudy top 2/3 of the frame, the camera’s initial evaluation of the scene results in a rather dark image – especially if we are judging this by the exposure of our subjects in the bottom of the frame.
Understanding that the camera will assign more priority to the sky which takes up 2/3 of the scene we can make a manual exposure compensation adjustment which tells the camera to brighten up the scene by +2/3 and then +1 full stop which results in a better overall exposure.
Again, in aperture priority this is achieved by a change (reduction) in the shutter speed which allows more light to fall onto the sensor. Sometimes the exposure compensation adjustments may result in a less than optimal shutter speed (eg less than 1.focal length0 which may then in turn require you to increase your ISO.
It all comes back to Aperture, Shutter Speed and ISO.
Example 3: Creating Mood in an Image
One of the reasons that photographers love that early morning and later afternoon light is the fact that it creates depth in a scene. it is often the keylighting that falls on a subject whilst the rest of the frame is dominated by the long shadows that adds that little something extra to a scene.
Evaluative metering, by virtue of the fact that the entire scene is evaluated, often ends up washing out these kinds of scenes as the camera tries to bring back details into the shadows. The example of this young hyena photographed in the early morning light is a great example of how some sort of manual exposure compensation is need in order to preserve and enhance the mood of the scene.
Underexposing by 1 full stop here darkens all of the shadows in the and really makes our subject pop from the scene. Without exposure compensation the shadows become a washed out grey and the bright light falling onto the hyena almost results in our subject being a bit overexposed.
Another example from the Kafue National Park shows how underexposing what is predominantly a dark scene with soft keylighting results in an image with a lot more mood.
Apart from preserving the details in the fine areas of white on the chin, underexposing makes the dark areas darker and just makes the areas with good light more prominent.
Example 4: Sunrise & Sunset
How many of you have heard that you should meter off of the brightest part of the sky for a sunrise/sunset image?
This is quite right and assumes that you’re in spot metering mode really. Again, looking at how the camera will evaluate this scene we have a ball of bright orange and a predominantly dark landscape. The camera, in evaluative metering mode, will try to find an exposure which copes with the bright sun whilst trying to expose/preserve some of the details in the shadows. The result, a washed out scene with an overexposed sun.
Underexposing by a full stop (-1EV) preserves more of the highlights in the sun and preserves more of the yellow, orange and red tones. Underexposing by two full stops (-2EV) does so to an even greater extent. Perhaps too much so.
Which is correct?
That’s up to you and what you are wanting to capture and create.
By understanding how the camera works in evaluative metering mode I am able to replicate the results that would have been achieved in spot metering mode by making the necessary adjustments via manual exposure compensation.That being said, there is still a place for spot metering…
Spot Metering & Spotlights
Spot metering and spotlights are a match made in heaven when it comes to wildlife photography.
As I mentioned in the initial post, the correct use of spotlights results in a scene with an extreme range of light intensity and, when left in evaluative metering mode, the camera has to battle between exposing the bright areas where the light is falling and the pitch black areas where there is no light. Most of the time the majority of the scene is dark which means that the camera favours these darker areas and will inevitably settle on a slower shutter speed in order to “expose” these shadows.
- A slow shutter speed which ends up producing a blurred image
- The areas where light is falling being overexposed into a bright mess
Not ideal. Whilst you could always tell the camera to underexpose this scene and underexpose by a full 2 stops (-2EV) or more, spot metering is a better option.
In these examples you will see that my spot metering has been linked to the active AF point (a feature on some of the more advanced camera models). In spot metering mode the camera is ignoring the darker regions and only using a small part of the frame to give you a an exposure reading.
I also prefer to shoot scenes like this in Manual mode as the light source is not changing much and aperture is almost always set to being wide open (eg F2.8) to allow as much light in as possible. In this manner, the camera’s light meter is still giving me a reading based on the location of my focus point and i can control whether I want to under-expose or over-expose by adjusting my shutter speed. A faster shutter speed results in a dark (under-exposed) image whilst a slower shutter speed results in a brighter (over-exposed) image.
In this manner, one can essentially trick the camera into ignoring all other light within a scene and meter solely off the brightest part of the scene.
I’m not saying that spot metering isn’t useful in any other situations. I just prefer, and find it easier to make the necessary adjustments to exposure using manual exposure compensation. Lets say for example we have a leopard in the shade draped over a branch with bright light in the background. We have two options:
- Switch to spot metering mode and ensure that our spot metering is linked to our AF point (If not we need to lock exposure using our central focus point before recomposing)
- Simply overexpose by probably a full stop (+1EV) in order to correctly expose the subject.
There was a comment left on Facebook on the metering post which went something along the lines of “This method is irrelevant as exposure can be adjusted by 2 full stops in either direction in post-processing”. Whilst exposure can be adjusted after the fact, your goal should be to get it right in camera first and not rely on various post-processing techniques to make up for your mistakes in the field.
Hopefully these two posts will help you to understand what is going on in the camera when it is metering a scene and how you can take control and ensure that you capture a scene as you want to. As time progresses you’ll become a lot more familiar with the exposure values needed to handle various scenes which require some sort of exposure compensation adjustments.