New to photography? This is a must read!!

What are the basic technical parameters you need to set when taking a photograph?

The art of shooting a picture lies in capturing what you actually see and putting it on the screen or on a piece of paper to resemble what you wanted to express at that moment. Your camera, your equipment is just the means. In order to better tell your story, apart from aesthetics, you need to know how to use your equipment. This guide is all about that!

Although most users believe the number of Megapixels is the one and only important factor and the more the better, this is not true. This is a marketing trick camera companies have got into to make buyers change their products frequently as the bigger number for some reason implies better quality.

The number of Megapixels (1Mp = 1.000.000 pixel) in your camera sensor is only important if you are going to print your pictures (and print them REALLY big) or you do a lot of cropping (cutting bits and pieces of your photos). Actually around 8 Megapixel for a common user that just stores photos in a PC or prints them in 8x15 format is just enough. What is more important is the surface of the sensor and secondly the pixels on it. Think about it. A sensor on a mobile phone that is 5x4 mm and 10Megapixels I highly unlikely to be of better quality than the same number of MPs on a surface of 36x24mm sensor. A single pixel on the second (which is a the standard on most high end DSLR cameras) can capture and process the light much better than a single pixel on the first one because each pixel has a bigger surface.

Anyway, the 4 most important parameters that you need to always set when taking a picture are:

• Exposure time (how long?)
• Aperture (how much?)
• ISO (how sensitive?)
• White balance (what color?)

The three first alone are grouped under one term, Exposure triangle.

There are more parameters that you can set (and you should know about!) but let us start with the ones mentioned above.

Before we start lets understand the basics of a camera with the following illustration of a digital camera:

Shutter closed

Shutter open

Setting apart the technical details of a camera the principle is simple and has not changed much since it was first invented 150 years ago.

Lens: This is a system of glass elements and other moving parts (shutter and stabilization mechanism), that straightens up the light before it hits the sensor. It is very important that your camera has a good lens as this will determine much the quality of the final picture. All the zooming and aperture is done in the lens

Shutter: Shutter is like a curtain that is always closed and prevents light from hitting the sensor. Once the shutter release button is pressed this curtain briefly opens to allow light pass and activate the light sensitive elements on the sensor

Sensor: This is where the heart of your camera beats. It is where the film used to be in old film cameras. It is a complicated system of light sensitive elements that get activated with light. This is where the image is created.

Major difference between the modern day sensors and films is that films were the place where the image was created and it stayed there until development. Sensors store nothing. Once the image is created it is moved to the Memory card

Memory card: This is the image final destination and where your data is stored permanently. You can remove it and view the pictures on your PC, photo frame etc. It works like a small hard disk, without the moving parts

Let’s now have a look at the basic parameters in more detail:

Exposure time

When you think about exposure time think about “how long”. Exposure time is how long the shutter will remain open. It is measured in seconds and in most cameras is a number ranging anywhere from 1/4000 (of a second) to 30”. The smallest the number the least time the shutter remains open to receive light. On a bright sunny day, shooting outdoors in midday you will need to set a number closest to the 1/4000 whereas to shoot in a dark night the stars you will need to leave your shutter open for 30”. Be aware that above 0.5 seconds you will probably need to place your camera on some steady surface as even the slightest shaking of your hands will cause your picture to turn out blurry. 

One more setting available on most high end models is “Bulb”. Using this setting, the user decides how long the shutter is going to remain open for. So on a really dark night, if you want to shoot the star trail you can leave the shutter open for hours…!

Aperture

This is a crucial parameter to set in your picture and it holds the “how much” will your shutter open to let light into the sensor. Usually you can find that number written on the lens of the camera and it is displayed in various ways and some examples are: 1.4, f2.8, f/22 etc.

The smaller the f number, the wider the shutter opens and more light reaches the sensor.

Shutter

The bigger the f number, the narrower the shutter is opened and less light reaches the sensor.

You can create interesting compositions depending on the aperture that you use. When all the elements in your composition need to be crystal clear you will use a big f number. If you want to take a picture with a shallow depth of field (blurred background but crystal clear foreground) open up the aperture (small f number).

The safest f number to set when taking simple landscape, city etc pictures is f8.

f1.4

f16

When shooting in dark environments and tripod is not an option, remember to use a small f number so more light is allowed in your sensor!

ISO

The ISO (standing for International Standards Organization) is a remainder of the film era when the photographers of that time, depending on how much light they were planning to shot, they had to buy and use different film with various sensitivity levels. There were various standards to measure sensitivity (called sensitometry) but ISO prevailed. This sensitivity is an important factor of modern day sensors. 

ISO is a number between 100 and 6400 in most cameras (most powerful sensors have a span of 50 to 204000!). The lowest the number the less sensitive to the light the sensor. This means that more light is required to capture a shot. The higher the ISO the less light required.

In really dark conditions, using a high ISO will result a brighter shot and you might get away with needing a tripod. But there is a catch: Apart from expensive cameras with large sensors, using a high ISO (anywhere above 800) will result in your picture having grain. And as this number grows, the more grain you are going to notice in your pictures. So really crank your ISO if there is absolutely no other way to take your shot.

Notice the grain level on the 3 pictures which were shot using the exact same aperture, f4 but different ISO numbers.

ISO 100

ISO 5000

ISO 25600

Exposure triangle

Unless you are using one of the automatic settings, the three parameters described above (exposure triangle) will determine how your picture is going turn out to be. One step before pressing the shutter button you should check the exposure meter of your camera. On most will look like the one below and the picture is well exposed if it the pointer is in the middle of the scale. The closer to the + symbol the more overexposed your shot will be. On the other side it will turn underexposed.

Exposure meter

It is generally a good idea to slightly overexpose your pictures.

White Balance

White Balance is the only one of the parameters described here that you need not to be extremely careful with as if you get it wrong you can repair it quite easily in post processing software (like Photoshop). If you do not plan to work on your photos, then you should set the white balance in advance.

So what is white balance (or color balance)? Every object that does not emit light (like the sun, lamps, etc.) simply reflects the light that it receives from a light source. This light has certain temperature that is measured in the Kelvin scale. The human eye does not understand the difference in temperature between different light sources because it can easily adjust (although anyone can tell that a fluorescent lamp is “colder” than a tungsten one).

The camera, unlike the human eye, cannot understand the difference in the source light and will adjust depending on what it thinks is the best setting. Although the automatic setting will work in most cases, it is good to set the white balance to one of the pre-defined settings (sunlight, cloudy, tungsten, shadow etc). That way the camera will know beforehand what the temperature of the picture will be and make necessary adjustments.

In high end models users can set the white balance by holding a gray card in front of the lens. This neutral color card, reflects the ambient light and the camera understands what the color temperature is and therefore adjusts the white balance with great accuracy.