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still have lots of questions about my power shot sx150, still dont understand shutterspeed,aperture


really need to understand shutter speed and iso and aperture...tried and my screen and the pics got darker the higher i set the shutterspeed,why???



When you set the shutter speed to a higher value, it means that you are taking a picture FASTER. To explain why it is darker, realize that there is a sensor behind the shutter and the longer the sensor sees light, the brighter the picture will be. Similarly, the sensor is not exposed to a lot of light when you set it to a high shutter speed.

ISO is the sensitivity of the camera's sensor to light. The higher the ISO, the more grain/noise there is in your picture, but you will be able to shoot at faster shutter speeds because the ISO compensates for the less amount of light your sensor is exposed to. When you set it to a low ISO, you will have less grain/noise but you will have to decrease the shutter speed in order to expose your sensor to more light.

Aperture is the opening of your lens. If the lens has a small aperture (I.e. a high F value - f/8), less light will come through the lens and consequently, the sensor will be exposed to less light. Thus, making your pictures darker (in comparison to a low F stop). A high F value also leads to a sharper picture (i.e a deeper depth of field). For landscapes, a good rule of thumb is shooting with f/8. When you shoot with a lower value of aperture, the lens opening is larger. You are allowing more light into your camera and will make the picture brighter. A small F value will lead to a shallow depth of field. It is a good idea to use a smaller value for portraits and for low-light situations.

In short,
↑ shutter speed, darker picture
↓ shutter speed, brighter picture

↑ ISO, brighter picture
↓ ISO, darker picture

↑ Aperture, darker picture
↓ Aperture, brighter picture


Read this article & see if it helps explain the basics well enough to get you started on the learning curve.


A good photo requires several things to be set or done correctly & thanks to internal computers today's cameras can help with the other settings when you pick the most important one for the situation. For action that's the right shutter speed, for low light ISO may be the one you need to manually set, and for control of the depth of field (what's in focus front to rear of the shot) you choose an appropriate Av setting.


"A skill is developed through constant practice with a passion to improve, not bought."