Photography in recent times has become a very casual hobby that anyone can get into, thanks to the rapidly developing camera technologies that are affordable and easily available to everyone.
With advanced technologies and 'automatic' functions built into the cameras, it might sound silly when you hear someone saying 'You gotta shoot manual!'.
As silly as it sounds, the truth is that all serious photographers shoot in manual mode in their cameras. The reason being, that you will be in total control! There is nothing wrong with shooting on auto mode. However, one will not have control over the exposure and other aspects of the image. In some cases, the photograph when shot in automatic mode may not be desirable due to inaccurate image processing. Furthermore, various techniques of photography (ex: long exposure) require specific control on how the sensor captures light, which is only possible when shooting in manual mode.
Before we get started, there is another important term that is commonly used in photography- Exposure. Exposure is simply the amount of light reaching the camera sensor. It basically refers to how bright an image is. The verb exposing is often used to describe the process of taking an image.
Let's first understand the phrase 'shooting manual'. Three basic factors that affect a digital photograph are Shutter Speed, Aperture, and ISO. Hence, the above three parameters collectively are known as Exposure Triangle since each of them is responsible for controlling the amount of light that is captured by the sensor.
When these three parameters are set manually by the photographer then it is said to be shooting in manual mode.
The three parameters directly affect the amount of light being sensed, hence deciding how bright or dark an image is. Apart from this, each of them also has a secondary "consequence" on the photograph.
Shutter Speed
It is the amount of time during which the sensor captures light.
it is measured in seconds (usually a fraction)
The longer the shutter speed, the more the light that is captured, and therefore the brighter the image is.
Its secondary function is to control the 'motion blur'
Shutter Speed is a unit of time measured in seconds and a fraction of seconds. A faster shutter speed has a smaller value of time ex: 1/500s while a slower shutter speed has a larger value ex: 1/50s. Naturally, the smaller values(1/500) of shutter speed have a lower exposure as compared to the larger values (1/50s).
In the above pictures, only the shutter speed was varied keeping the remaining parameters constant. As expected, an image with a slower shutter speed (left) is brighter than the one with a faster shutter speed (right).
The secondary function of shutter speed is motion blur. Since shutter speed determines how long a sensor captures light, it affects how moving objects are captured.
To put this into perspective, try a quick exercise with your eyes. Slowly blink your eyes while moving your hand in front of your face. Observe how the hand looks. Now repeat the same but while blinking faster. You will notice that when you blink faster, your hand seems to 'freeze'.
The camera sensor works similarly, a slower shutter speed 'captures motion' and therefore a moving object appears to be blurred. On the other hand, a faster shutter speed has the ability to "freeze motion", and hence a moving object is sharp and not blurred.
As seen in the images above, there is evident motion blur visible near the hands and the fabric. This motion blur is absent in the image with a higher shutter speed.
This effect of motion blur can be both desirable and undesirable. A usual rule of thumb is that, when working with fast-moving subjects such as in sports photography, wildlife, etc, a faster shutter speed is used and while working with slower-moving objects and to achieve creative styles such as landscape photography, astrophotography, and long exposure photography a slower shutter speed is used.
It is a good practice to make use of a tripod when dealing with lower shutter speeds, otherwise, the images may be spoilt due to the shaking of our hands.
Aperture
Corresponds to the opening of the lens.
Larger the opening of the lens, the more the light that enters, resulting in a brighter image.
Measured in f stops
The secondary function is to control the Depth of Field
The aperture of a lens is synonymous with the pupil of our eye. It is varied to control the amount of light entering our eyes. A wider opening corresponds to more light entering while a narrower opening corresponds to lesser light entering the lens.
Aperture is expressed in terms of F-numbers. It is the standard format followed in photography.
an F-number is expressed as
->"f" written in the numerator
->a number in the denominator
f/1.8, f/2, f/4, f/8, f/10, etc are a few examples of various f numbers used.
So what do these f numbers mean?
An F number with a smaller number in the denominator corresponds to a large aperture while an f-number with a big number in the denominator corresponds to a smaller aperture.
f/1.8 Large Aperture (more light)
f/2
f/4
f/8
f/16
...
f/32 Small Aperture (less light)
In the above pictures, only the aperture was varied keeping the remaining parameters constant. As expected, an image with a larger aperture (left) is brighter than the one with a smaller aperture (right).
The secondary function of aperture is to control the Depth of Field. Simply put, it is the distance before and after the point of focus that is sharp. Here is an illustration to understand it better.
Aperture and Depth of Field are inversely related, Implying that a large aperture gives a small depth of field while a small aperture gives a large depth of field.
As you can see in the above images, the image with a large aperture (f/1.8) has a sharp subject with the background and foreground being blurred. This is a consequence of a shallow depth of field. In contrast, the image with the smaller aperture (f/10) has a wide depth of field which is why the majority of the leaves in front and behind the subject are also in focus.
Both narrow and wide depth of fields are desirable depending on what type of scene is being shot. Usually portraits, and close-up shots of subjects like animals, etc make use of a narrow depth of field since the importance is given to a singular object. However, when the photograph tends to tell the story of a complete scene like a landscape or a gathering, deep depth of field is used to bring everything in focus.
ISO
Controls the light sensitivity of the sensor
Lower the sensitivity of the sensor, a lesser amount of light is captured resulting in a darker image.
Expressed as a number
The secondary consequence of ISO is Digital Noise
ISO is a standard parameter of all digital image sensors and is used to regulate their sensitivity to light. It is measured in ISO numbers and their range varies across different camera sensors.
ISO 100 Lower sensitivity (less light)
ISO 200
ISO 400
ISO 800
....
ISO 56000
ISO 128000 Higher sensitivity (more light)
An image shot at a low ISO(200) is darker compared to the image shot at a higher ISO(640)
Apart from ISO controlling the exposure, it also affects the noise in the picture. We can understand noise as the unwanted disturbance that occurs in our picture due to the working of electronics of the digital sensor. As we increase ISO, we increase the sensitivity therefore the digital noise also increases. This digital noise affects the quality of the photograph.
Noise is very undesirable in any image. Therefore it is a good practice to shoot at the lowest ISO possible. ISO needs to be adjusted for exposure only as the last resort. The amount of noise at various ISO numbers is different for each sensor. It is important to understand your camera by experimenting with it and determining the maximum ISO number after which the digital noise is unacceptable.
Hey There! Thanks for reading till the end. Feel free to try out the various concepts I have mentioned. If you would like reviews of your images you can reach out to me on Instagram or here. You can also tag my Instagram handle @kshitij.madduri while posting your pictures for a shoutout.
#photography #photographytips #learnphotography #mobilephotography #exposuretriangle #manualmode