Understanding shutter speedImportant information about shutter speed - A Quick Glance:Shutter speed --> Length of time the shutter is kept open.
Fast shutter speed --> Less light falls on the sensor. Use flash or natural (sun) light to ensure your images don't turn out too dark or underexposed.
Slow shutter speed --> More light falls on the sensor. Great for low light situation, but not for moving subject where you want to freeze the action. When slow shutter speed is selected, select a low ISO value, as low as 100.
Shutter priority [Tv Mode - Time Value] allows the photographer to choose a shutter speed, then the digital camera automatically sets the aperture to suit.
Fast shutter speed ...................................Slow shutter speed
1/4000, 1/2000, 1/1000, 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8, 1/4, 1/2, 1 second
--> Doubles amount of light ...........Halves amount of light <-- Each standard increment either doubles the amount of light (longer time) or halves the amount of light (shorter time). A typical shutter speed for photographs taken in sunlight is 1/125th of a second.
When to use fast shutter speed? 1. When capturing water flow, if you want to capture every bead of water. For example, use 1/60 of a sec.
When to use slow shutter speed? 1. If you want to blur running water, to show an impression as if it is a continuous stream of water, use slow shutter speed like 1/4 of a sec.
2. To freeze fast-moving subjects, for example at sporting events.
3. To take photographs of car light trails, use a shutter speed of 30 seconds.
Best photography tips for taking pictures of car light trails at night* Set your digital SLR camera to shutter priority. This is important for all night photography. Shutter priority allows you to set a slow shutter speed so enough light is let in to the sensor. If you don't do this, you will end up with a black image or one that only displays circles of light.
* Use a 30 second shutter speed or more. The slower the speed, the more light you'll see in your photograph.
* Because your taking the photograph with a slow shutter speed, you can now afford to use the lowest ISO setting possible. Therefore set your ISO to 100 (if your digital camera goes that low) to ensure the best quality photo with no grainy pixels or noise as it's also known.
* Sit your digital camera on a tripod to miminize the effects of camera shake. The sturdier the tripod the better. If you don't have a tripod handy, then sitting the camera on a nearby object would also work. As long as your not hand holding the camera.
* Use a camera remote to take the photograph. This stops blurred images that are usually a result of camera shake. Sometimes pressing your cameras shutter button can cause a small shift in the camera when you release it. In normal circumstances this isn't a problem. However, for night photography on slow shutter speed it can be the difference between a blurred photo or a sharp one.
* Wait for a night where there is no wind. This is especially important if your tripod isn't very sturdy. The slightest shake in your tripod can cause motion blur.
* Before you take the photograph, set your lens to automatic focus and focus on a far away object like the sky for example. You do this by pressing your shutter button half way down until you see a red dot flashing on the sky or far off object. Then turn off your automatic focus so it doesn't change from there on. Your now ready to take a perfectly focussed photograph. I have heard many photographers go to the scene they are going to shoot during the day and focus their lens before returning at night. However this seems rather tedious to me.
* Take more than one photograph. This is particularly important if you're not intending to return to the same spot again. I recently did some night photography taking 3 images of car light trails. Even though I didn't change the camera settings between shots, one photograph turned out much sharper than the other two. This is probably due to camera shake caused by wind as the weather wasn't the best that particular night.
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