Shutter speed

daveking

Hi, I want to know how I can get down to 3 or 4 seconds shutter speed on a D3200. What mode do I need to be in? I want to get night car trails, silky water look etc. I know I need ND filters, right?

bruto

You can go down to thirty seconds in manual or S mode, and if the scene is dark enough, A mode will choose a shutter speed down to 30 seconds. Of course to get a proper exposure you will need to darken your view substantially.

If you need a slower shutter speed than 30 seconds, you must use S or M, set the shutter to "bulb". Use the infrared remote shutter release, which will open the shutter on the first push, then close it on the second. Without that release, the shutter stays open only as long as you push the button, which is hard to do without vibration.

You can use an ND filter up to about three stops for a shutter speed that is still hand holdable, which will put a nice blur on waterfalls and the like, but not get the complete effect.

You can get ND filters strong enough to do more, but when you get very strong filters you'll be unable to auto focus or to see much through the viewer, so you will have to put the camera on a tripod, set up your shot, and then put the filter on. Square slide-in filters such as the Cokin system can make this a little easier but they can get pretty expensive. You can get a variable ND filter that helps a lot. They range in price from not so bad to very expensive too. With a variable ND filter, you can view, and set up the shot with the filter on, then turn it to darken.

You should be able to do night car trails without the filter. For that, you need to experiment to see how long you can leave your shutter open with a fairly small aperture, and still not get the whole scene too bright. Because car headlights are very bright, they will still show up even when the rest of the scene is dark. Some of this will depend, too, on what else is in the scene, but you can try a middle aperture, and a shutter speed in the range of 10 to 30 seconds. If there are buildings or street lights, they'll also produce a high glow, and the scene can end up with an eerie moonlit look.

For mode, manual is pretty much required for things like night car trails. For blurred motion such as water, you want the exposure to be more or less as the meter calls for, so manual or aperture priority will work. To make your shutter speed as low as possible, just close down the aperture. Smaller than f/11 or so may start to show some diffraction softening, but that may or may not be noticeable depending on what you're shooting.

Remember when doing manual work like this to turn off the Auto ISO, or the camera will second-guess your settings and set the ISO to max trying to brighten the exposure. You want the lowest ISO for the least noise.

There is a low speed noise reduction function also, which is probably worth putting on. This will double your exposure time, because it actually will take a second picture with the shutter closed, and use that as a noise mask over the exposure. It makes repetitive long shots impossible, but for single shots it can help a little. Just remember that it's on, so you don't freak out when every 20 second exposure stalls your camera for another 20!