Smartphones are now equipped with Cameras Increased performance allows you to click exceptional pictures that high-quality cameras are unenviable for. Among the parameters that must be considered when choosing one smart phone, So , technical features From the camera. Among these there is one to consider and it isAnd stop, I.e. the ratio of the focal length of the lens to the diameter of the pupil. Many may have seen it, but did not notice: this number is the number that the camera shows when resizing Aperture. Here’s what you need to know about f-stops and how it works.
F-stop, what is in photography
It is not enough to have one camera With outstanding features and press the button to take a beautiful photo. Every time you take a shot, a process begins Catch the light That comes from the scene we’re framing that hits the sensor. The metering of the amount of light that reaches the sensor is precisely determined Exposure. Too much light, or too little, will result in less-than-perfect shots, where some details will inevitably be lost.
There are three parameters that regulate the image exposure:
- The orifice or diaphragm, Which indicates the size of the diaphragm opening in the lens;
- show time, Which is the period of time the shutter remains open
- ISO, The parameter indicating the sensor’s sensitivity to light.
These three parameters in photography pose Width of the triangle-To get perfect shots without the auto, the photographer must know and master. If shutter speed is measured in milliseconds, aperture is measured And stopIt is a number we will certainly see already without giving much importance. When you choose a camera, in fact, the opening is also indicated among its characteristics, for example on iPhone 12 Pro Max it is f / 1.6 while the Samsung Galaxy S20 Ultra has an f / 1.8 f-stop.
F-stop: how it works
AgoAnd stop It is the ratio between focal length and aperture, i.e. the aperture that light enters through, and changing this parameter means getting bright or dark shots. If you have an f-stop f / 2, that means if you have a lens with a focal length of 100mm, the aperture will be half that, that is, 50mm. A lens with a focal length of 200mm will have a aperture of 100mm. This means that the lower this value, the higher it is Opening size Hence the amount of light that goes in, allowing you to get brighter shots as opposed to f-stops, which instead indicates a narrower aperture and darker photos.
For example, suppose you took a photo of an outdoor object with two different 100mm and 200mm lenses, both with f / 2 stops. Despite the difference in the aperture of 50mm and 100mm respectively, the two images would be bright, because despite The aperture is double for 200mm lens, the field of view is half the focal length of 100mm. And the effects on the sensor cancel each other, resulting in the gain The same brightness It is denoted by the f-pause ratio.
F-stop: as used in photography
To get a good quality shot, you have to take it into account Width of the triangle, To ensure that the result is not too dark, or Poor exposure, Or too bright, or Overexposure. The amount of light hitting the sensor is indicated in the image.StopThis is a dimensionless value. If you want to increase the amount of light by one “stop”, which means doubling it, you will have to act according to the exposure time, and use a wider aperture or a different ISO.
for every Image balance To obtain the desired shot, it will be necessary to understand which of the three parameters of the intervention are from time to time according to the needs. For example, using a wider aperture increases brightness, but it risks blurring background detail – a great solution if you want to take a photo, less so if you’re trying to take a panoramic photo.
So the f-stop is not measured on a linear scale, but on a scale Logarithmic scaleSo going from f / 4 to f / 2 will not only double the amount of light entering the camera, it will quadruple. Because of this, f-stops are often indicated with incorrect numbers – doubling the amount of light entering f / 4 requires you to use f / 2.8.
F-stop: how to use it with smartphones
If it is for cameras F-stop value It can be set manually, in the case of cameras with smartphones, it is Fixed value. Therefore, in smartphone cameras, to balance the shot, you cannot act according to the f-stop, but to increase the amount of light entering the sensor, you must act on Shutter speed and onISO. Also, using faster shutter speeds will result in less blurry shots, while lower ISOs will result in much better quality.