What is Focal LengthI created a diagram to help you understand what is focal length. An explanation of focal length will help you when you are considering buying a camera. In layman's terms, the definition is the distance from the center of the lens to the focused image on the sensor. A longer length would mean that it is more of a telephoto lens. In the diagram, if you can imagine a longer lens would mean a narrower angle of view of the subject. In other words a smaller amount of the subject would be focused on the sensor.
Most cameras come with a zoom lens, which means you can essentially change the focal length of the lens. Zooming in narrows you angle of view and brings your subject closer. Zooming out widens the camera's view, includes more things in your viewfinder and make them smaller. The chart below is for a full frame or 35mm size sensors. Point and shoot cameras have smaller sensors and so the actual distances in "mm" millimeters is smaller. Usually the camera maker will give you the equivalent numbers for the zoom.
If it says it has a 4x zoom, it's range may be the 35mm equivalent of 25-100mm zoom. A 10x range might mean 28-280mm zoom. Tomorrow, I will take some photos with my Canon 5d and show the different amounts of zooming. You can see the usual uses for each range of lenses in the chart above. Camera Lens Comparison. Here they are: the sample photos showing 4 different focal length settings. These are not strict guidelines to follow, just typical uses for certain lens types. If you have any questions, feel free to ask and I'll write an article when I get a chance. What is a Prime Lens. A zoom lens gives you many focal lengths to choose from while having to use only one lens. What is a prime lens and why would anyone want to use one. As always have fun as you discover more digital photo tips on my site and also try to get better at avoiding photo mistakes. Best wishes, Photo Tip Man Back from What is focal Length to Photography Definitions
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