The basics you need to take a good photo

Believe it or not, it takes an understanding of 3 things to be able to take a good photo.

• Aperture
• ISO
• Shutter Speed

The aperture is responsible for how much light can flow into the camera.

Shutter Speed specifies how long the exposure time will be.

ISO, on the other hand, is the light sensitivity. 

All three elements belong together and must be understood in order to know how to adjust them in any situation.

To go into more detail: 

Aperture:

It is displayed with a f on your camera, for example: f/4.0 = aperture 4.0 

The range depends on your camera lens. 

The smaller the number, the more the aperture is open and more light can flow into it. There is not much depth into the pictures and backgrounds will blur and get a bokeh effect. Perfect for portraits!

The higher the number, the smaller the aperture is open and less light can flow into it. Photos will have more depth and the background will stay sharper. Perfect to capture landscapes! 

ISO: 

Light sensitivity is an important setting to control.

At low ISO, the sensor is less sensitive to the incident light. This means that you have to expose the photos longer. At times of day with good lighting conditions, low ISO numbers are optimal for good image quality.

High ISO value: Dark light situations require a higher ISO value. The higher the light sensitivity (high ISO value), the shorter the exposure time. 

In animal or sports photography, you have a short exposure time because there is a lot of movement involved. Here it is recommended to increase the ISO, but be careful! A high ISO also has its dangers! The higher the ISO, the higher the image noise. It’s best to have a low ISO to ensure good quality.

Shutter Speed:

It depends very much on the subject as well as the lighting conditions to choose the perfect exposure time.
For fast objects (like animals, sports) short exposure times should be chosen.
For non-moving objects, you can also expose for a longer time. Here it is recommended to use a tripod, because a picture can quickly look blurred. A tripod is indispensable, especially for night shots, if you want to expose for several seconds. Even at 1/60 seconds, you can hardly guarantee razor-sharp photos without a tripod. 

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„Cambridge in Colour“ gives a good overview and also a very nice table that indicates what shutter speed can be used in which situation.