I have a Canon PowerShot SX500 IS. However, when I shoot in manual mode at a high shutter speed the images are very dark, almost black. On the other hand, when I use a lower shutter speed later in the day the images come out all white.
What are the possible causes of these problems?
If you change to an all manual mode, then it’s expecting you to adjust shutter speed, aperture, and ISO all in concert - 'manually'. If you set a faster shutter speed, you'll need to raise your ISO or open your aperture more to adjust for the fact that you're letting in less light. The same with a lower shutter speed.
If you're going to go all manual, you'll need to adjust all three (or at least two). Try a mode like Sv (shutter priority) mode. You can set the shutter speed and it will attempt to alter the aperture for your selected shutter speed.
When taking a photograph, the image isn't created immediately, but over time. A higher shutter speed provides less exposure to the light, and thus the resulting image will be darker than a slower shutter speed that allows greater exposure, if all settings are the same.
This can be compensated by making your camera more sensitive to light (raising your ISO, at the cost of noise), allowing more light through your lens (by widening the aperture), or lowering the shutter speed to allow more time.
To help guide your decisions, there is usually a meter towards the bottom of the viewfinder. When its marked in the center, this generally means you should get about the right amount of light.
Shutter speed is one of the things that control aspects of your image, primarily in your case it is effecting how much light is let into the lens. In manual mode you have to adjust all of your settings yourself as manual implies. So when you are using these shutter speeds you are not compensating for the other settings and that is why.
Experiment with Automatic and Shutter Priority mode to gain a better understanding of this.
Overexposed and underexposed photos are results of not exposing your scenes correctly. When you use high or low shutter speeds, you have to change the aperture and ISO, as well! If you raise up the shutter speed, means that less light will enter the sensor, so you have to change the aperture or the ISO or both of them. An aperture of f8 lets less light to get in, whereas an aperture of f2.8 is widely open to let in more light. Also, ISO numbers play an important role. ISO 800 makes the sensor more sensitive, in order to receive more light, while an ISO 100 makes the sensor less sensitive and the pixels of the sensor will ''absorb'' less light. All these (Shutter speed, Aperture and ISO) makes the Exposure Triangle.
In short, in order to gain a good exposure, you have to balance the shutter speed with the aperture and the ISO. These three parameters work together to help you avoid an overexposed (too light) or underexposed (too dark) picture.
Hope that helps!
