Camera Basics: Turn off Auto!

  • 13/05/2015

I love meeting photography enthusiasts who are beginning their own journey into photography; it’s new, it’s exciting and there are no limits. In my workshops I’m often bombarded with the technical questions (which I welcome!), and although learning by doing in the moment with examples is great, it often helps when you have something to read over repeatedly and go through the motions yourself after it sinks in. It is my hope then that this guide will come in handy when you’re out in the field, to explain some aspects of your new toy.

Tony’s Photography Essentials 101; A crash course for any beginner in better understanding the camera for the first time. It’s time to take the camera off AUTO and claim full control of your DSLR!

Essentials:

1. Shooting Mode
2. ISO
3. Exposure Triangle
4. Metering
5. Focusing

1. Shooting modes

On top of most cameras is a rotational dial with various symbols and/or letters. With different camera manufacturers, come different abbreviations but the shooting modes available are essentially the same.

ZPR-NIKON-D750-TOP

It is here where we control the shooting modes and whereby the selection made determines the type of photo potentially achievable after pressing the shutter.

AUTO
In automatic mode (Green symbol in above image) all aspects of the photograph are determined by the camera; exposure, aperture, focus, light metering, white balance and sensitivity. Although technologically efficient in their own right, cameras do not always create the image you may envisage, and as a result I avoid using Auto mode myself; I prefer the additional creative freedom found in Manual mode (explained further below) to tweak each parameter specifically.

Aperture Priority (Av / A)
It is essentially a semi-automatic shooting mode. With this mode enabled aperture is manually controlled as the camera automatically corrects shutter speed accordingly.

If this word aperture is foreign to you, then technically speaking, it relates to the size of the opening in the lens through which light will pass when the shutter is open. With a larger aperture, more light will pass through, and conversely, a smaller aperture, results in less light passing through the lens. It is measured by ‘f-stops’; a ratio of focal length over diameter of the opening of a lens:
– Larger aperture (wide opening) has a smaller f-value
– Smaller aperture (small opening) has a larger f-value
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When the aperture is changed it directly alters depth of field (D.O.F) – i.e. the amount of an image in focus. A large D.O.F (small aperture / large f-stop) creates images where most of a scene is in focus. This type of aperture setting is typically good for landscape photography. Conversely, with a shallow D.O.F (large aperture / small f-stop) the subject is the only thing in focus, with the background soft and out of focus. This type of aperture setting is typically good for portraiture and wildlife for the ability to isolate the subject from the background.

Essentially, using this mode allows for control of D.O.F, whilst the camera compensates and does the rest.

Shutter Priority (Tv / S)
Another ‘semi-automatic’ shooting mode. This time shutter speed is controlled whilst the camera takes care of the aperture. Shutter speed, measured in time (fractions of a second, seconds, and even minutes if using “Bulb” mode) is the duration the shutter stays open during a photograph. The longer a shutter remains open, the more light passes through to the sensor. A short shutter speed is best for freezing fast moving objects and is best suited for sporting events and wildlife. Conversely, a long shutter speed is best for blurring moving subjects and scenes with waterfalls, cars moving at night for light trails, or fireworks. A sturdy tripod (unless resting on something immobile and holding perfectly still) is essential for capturing images requiring a longer shutter duration as any camera shake will create undesired results.

Essentially, this mode allows for control of suitable shutter speed duration for a given scene whilst the camera corrects the aperture for an appropriate exposure.

Program (P)
This mode is the convergence of both aperture and shutter priority mode with manual mode. Program mode enables control of either aperture or shutter speed mode, whilst the camera adjusts the alternative to correctly exposure the image.

Essentially, change one, the other changes, but you don’t have to keep changing between shutter and aperture priority modes to change either. As a result there is some additional freedom albeit still with restriction.

Manual (M)

Manual mode is all you. You have total control over exposure, aperture and shutter speed. The power is in your fingertips and you are free to set them as you wish. The exposure indicator meter in your viewfinder (or on screen if live view is enabled) will help guide you if your shot is over or under exposed.

As mentioned earlier, this is my preference. This is the mode I learned with as it allowed me to fully understand the impact of the different settings and allowed for greater creativity. It’s the mode I use today, and why it’s my recommendation you explore its capabilities as early on in your journey as possible.

  1. ISO

This is a measure of how sensitive a camera sensor is to light. It originated in film photography; depending on shooting conditions, specific film of varied sensitivities would be used. This concept is carried over into digital photography whereby ISO sensitivity is represented numerically typically from ISO 100 (low sensitivity) and upwards to beyond 6400 (high sensitivity); it controls the amount of light necessary for the sensor at a given exposure. In essence more light is required at low sensitivities to achieve a given exposure whilst less light is required at higher sensitivities for the same exposure. The bigger a camera sensor, the better quality photo achievable at a higher ISO.

As a rule of thumb, keeping the ISO low will reduce picture grain (noise) and produce the highest quality image (useful if you want large prints). In a well lit environment (i.e. daytime outside) the correct exposure is likely achievable at a lower ISO (i.e. 200) where there is ample light hitting the sensor and thus reducing its necessity to be sensitive. Conversely in a poorly lit environment (i.e. inside or at night) the correct exposure is likely achievable at a higher ISO (i.e. 800) where the reduced light hitting the sensor is multiplied to increase sensitivity. Incidentally, as aforementioned, an image will likely have increased noise which will reduce the overall image quality – this is more noticeable in darker/shadowy areas of an image and when printed in a large size.

3. Exposure Triangle

Aperture, shutter speed and ISO comprise of what’s known as the “exposure triangle”. Collectively, they control the amount of light entering the camera (aperture and shutter speed), or the amount of light necessary at a given exposure (ISO). As these three elements are intrinsically linked to a correctly exposed photograph, an understanding of their interwoven relationship is essential for controlling your camera. If one setting is changed, the other two elements will be influenced. Understanding their relationship to each other is another tool in your arsenal to better mastering your DSLR.

Aesthetic_Exposure_Triangle2

This essentially will come down to trial and error and knowing the basic effects altering aperture, shutter speed and ISO will have on an image. Use a tripod in scene that is likely to remain constant (i.e. inside focused in your kitchen with the lights on), and take an initial photo. Then change the aperture to various settings, then the shutter speed, and then the ISO. Notice the differences, and when there’s a balance where they are correctly exposed it is likely that your metering will be correct, which is the next aspect to consider.

  1. Metering

When the settings (aperture, shutter speed, ISO) above are tweaked the camera processes for the scene and tries to calculate average exposure, for both bright and dark areas. It averages the tones, a middle grey which is 18% averaged grey from the scene.

This is termed metering, and it accounts for why, depending on the scene, an image will be potentially darker or brighter than in actuality (what you see). That’s due to the average scene being exposed, which is correct most of the time. The in camera viewfinder or Liveview screen will depict this on a scale that changes for under or over exposure depending on settings.

images (1)

In continuance with exploiting the creative abilities in Manual mode and altering our settings we can also alter metering. There are typically three metering modes:

Average – The entire tonal contrast of an image from corner to corner is identified by the camera and exposed at 18% grey.

Centre-weighted – The centre of the scene is the focal point for exposure balance at 80% of the image, with the corners of the image not accounted for.

Spot metering – A specific focal point of a scene selected for approximately 5% of the area that is exposed and using the dark/light tones of that region, exposes the total image at middle grey tone.

  1. Focusing

Quite simply, the correct focus is essential. Irrespective of if an image is correctly exposed for aperture, shutter and ISO, if the subject of your image is out of focus, the photo will likely be undesired. There are a range of autofocus modes available within your DSLR but the most useful are the Autofocus- Single (AF-S) and Autofocus-Continuous (AF-C) modes.

AF-S 
Focus mode best for stationary subjects; Portraiture, landscapes, buildings, and any other immobile object.

AF-C 
Focus mode best for moving subjects; sports, wildlife, vehicles, and any other moving object or activity.

Focus points
To exploit these two focus modes, focus points are used to allow in camera processing to identify the focal target within the scene. When looking into the viewfinder focal points will overlay the view. These are a set of squares or dots that when selected on the back of the camera (become highlighted in red) indicate the active focal point within the scene of your image.

Nikon-D600-vs-Canon-6D-AF-Points

On many newer DSLR’s with up to 50+ focal points there is temptation to keep them enabled. I personally find that this is over zealous and does not allow for specific focal point focusing. As a result I always use a single focus point to ensure my subject is in focus. With the navigational pad on the back of the camera it is possible to choose different focal points within the same frame. This will potentially change the look of an image.

It is important to note that these focus modes are different to the Manual (M) and Autofocus (AF) functions on the camera and lens. Manual mode enabled allows for full focus control, whilst to exploit the AF-S and AF-C modes, AF must be enabled. Depending on your environment and scene they are all relevant. Personally, I have my camera and lens switched to Manual and don’t worry about AF-S and AF-C.

Summary
I hope this explanation on some major components of your camera helps you to discover how to move away from “Auto” and step into Manual mode and encourage your creativity flourish. Start slow and with more understanding of the significance of each setting your camera will become an extension of you. Before you know it, that shiny new toy will no longer be a mystery to you but a tool that allows you to get results, for that which you bought it for.