Lyceum Alpinum Zuoz - Workshop Level I - PHOTOGRAPHY

In the Beginning there was the Light

A photograph or photo is an image created by light falling on a light-sensitive surface, usually photographic film or an electronic medium such as a CCD or a CMOS chip. Most photographs are created using a camera, which uses a lens to focus the scene's visible wavelengths of light into a reproduction of what the human eye would see. The process and practice of creating photographs is called photography. The word "photograph" was coined in 1839 by Sir John Herschel and is based on the Greek φῶς (phos), meaning "light", and γραφή (graphê), meaning "drawing, writing", together meaning "drawing with light".

View from the Window at Le Gras (1826 or 1827), by Nicéphore Niépce, the earliest known surviving photograph of a real-world scene, made with a camera obscura.

Richard Photo Lab and Fujifilm: History of Photo

An alternative way to enter the world of images. Enjoy it!

Light, Speed and Stops: be ready to click, there's no time to waste!

The speed of light in a vacuum is 186,282 miles per second (299,792 kilometers per second), and in theory nothing can travel faster than light. In miles per hour, light speed is, well, a lot: about 670,616,629 mph. If you could travel at the speed of light, you could go around the Earth 7.5 times in one second.

Early scientists, unable to perceive light’s motion, thought it must travel instantaneously. Over time, however, measurements of the motion of these wave-like particles became more and more precise. Thanks to the work of Albert Einstein and others, we now understand light speed to be a theoretical limit: light speed — a constant called "c" — is thought to be not acheivable by anything with mass, for reasons explained below. That doesn’t stop sci-fi writers, and even some very serious scientists, from imagining alternative theories that would allow for some awfully fast trips around the universe.


What is a "Stop" of Exposure in Photography?

Exposure is controlled by shutter speed, aperture, and ISO speed. "Stops" let you directly compare and swap these to produce the image you want. In photography, a "stop" is a widely misunderstood concept, feared by many because it sounds so complicated. However, it's actually very simple.

A stop is a doubling or halving of the amount of light let in when taking a photo.

For example, if you hear a photographer say he's going to increase his exposure by 1 stop, he simply means he's going to capture twice as much light as on the previous shot.

Exposure: Aperture and Shutter Speed Explained

Exposure is the amount of light that reaches the camera's sensor (or film). If we don't get enough light we end up with a photo which is dark (underexposed). Too much light and our photo comes out bright (overexposed).

Aperture size and shutter speed add up to create our exposure. Learn how they work, and how to use them to get the creative effect you desire.

Exposure is a combination of two fundamental camera settings - aperture diameter and shutter speed. Many combinations will give the right exposure, but each will have differences is depth of field, motion blur, and so on.

This interplay of different factors can seem complicated, and people can be put off learning about exposure altogether, opting instead to use their camera's automatic mode to do the work for them.

However, your camera won't do nearly as good a job at figuring out the best exposure settings as you would, and this can result in photos which lack contrast and impact. Exposure is actually a very simple concept, and once you learn it you'll be able to take more control over your photos, producing better shots in the process.

So how do we control exposure? It all comes down to a combination of two basic camera settings - aperture diameter and shutter speed. Let's examine each in turn.

Light is not simply "white"...

What Does Colour Temperature Mean?

The technical definition of colour temperature is full of terms like "black-body radiator" and "chromacity space" - in short, it's very confusing, very boring, and above all leaves you feeling even more baffled than before.

In layman's terms though, different light sources produce different coloured light. For example, a candle emits a reddish light, while the midday sun's rays have a blue tint. These different colours can be expressed using a number, and this number is known as the colour temperature.

Colour temperature is measured on the Kelvin scale, which is denoted by the letter "K" or the word "kelvin" after the number. However, this is largely irrelevant - the only part we're interested in is the number.

You're probably wondering how all this affects you and your images. Well, the human eye is excellent at adjusting to different colour temperatures, which means that to you and me objects appear roughly the same colour whether they're outside in the sun or indoors under a lightbulb.

Digital cameras aren't as good at adapting as we are, and as a result they "see" objects as being different colours depending on the lighting. This can lead to our photos having a colour cast - that is, an overall blue or orange tint - which makes the shot appear unnatural and unpleasing.

Thankfully cameras allow you to correct for these colour casts by telling them the colour temperature of your scene. This is done using the white balance setting - simply tell the camera what type of lighting your scene has (daylight, shade, tungsten etc), and it will use an appropriate colour temperature.

For even more accurate control, some cameras allow you to program in an exact colour temperature in kelvin. You can get a precise value by using a colour temperature meter, or by taking a photo of a white object under the same lighting and letting the camera calculate the temperature. Alternatively you can make an educated guess using the chart below.

What is White Balance?

When we look at a white object our eyes will automatically adjust to the lighting conditions, so that the object appears perfectly white to us whether we are indoors under a tungsten bulb or out in the bright sunlight.

While our eyes are excellent at making this adjustment, digital cameras aren't, and the same object will appear different depending on the colour of light in the scene. This can leave our photos with a blue (cool) or orange (warm) tint.

White balance is the process of giving our camera a helping hand, so that it can reproduce the whites in our photo as they should be. Once it gets the white right, all the other colours in the scene fall into place, and we're left with an image that perfectly reproduces what our eyes saw.

Colour Temperature Chart

The following chart shows rough colour temperature values for a range of different conditions. The bar is coloured to show the hue and strength of any colour casts that might appear in your shot. Feel free to print it out and carry it with you to help you make quick adjustments on location.

Colour temperature can seem a tricky concept to learn, but once you get used to it you'll find it becomes second nature. It can be an invaluable thing to know, helping you cope with all manner of lighting conditions to produce photos which appear natural and well-balanced without the need for excessive post-processing.

Infographic: Indoors and Outdoors, two different kinds of light

10 Top Photography Composition Rules

There are no fixed rules in photography, but there are guidelines which can often help you to enhance the impact of your photos.

It may sound clichéd, but the only rule in photography is that there are no rules. However, there are are number of established composition guidelines which can be applied in almost any situation, to enhance the impact of a scene.

These guidelines will help you take more compelling photographs, lending them a natural balance, drawing attention to the important parts of the scene, or leading the viewer's eye through the image.

Once you are familiar with these composition tips, you'll be surprised at just how universal most of them are. You'll spot them everywhere, and you'll find it easy to see why some photos "work" while others feel like simple snapshots.

Composition in photography is far from a science, and as a result all of the "rules" above should be taken with a pinch of salt. If they don't work in your scene, ignore them; if you find a great composition that contradicts them, then go ahead and shoot it anyway. But they can often prove to be spot on, and are worth at least considering whenever you are out and about with your camera.