If your landscape images are lacking a certain something, you can use the power of a Neutral Density filter, to control time and introduce a sense of motion into the frame. A Neutral Density filter is a tinted piece of glass that fits in a holder in front of the lens and reduces the amount of light that can pass through the glass and reach the sensor.
This enables photographers to artificially extend the shutter speed of an exposure without the risk of overexposure and while the shutter is open, motion can be captured.
ND filters come in different sizes and strengths!
This technique can be used to great effect to transform crashing waves into a calm milky blur or rush hour traffic into trails of abstract light. However, for landscape photographers, ND filters can also be used to turn slow moving clouds into stunning streaks that add an extra layer of interest to the frame.
Not all ND filters are created equal. Quality examples do a much better job of preserving image quality, sharpness and colour. Cheaper filters may leave undesirable colour casts caused by the tint of the glass, but these hues can usually be corrected or minimised in software like Lightroom if you shoot in RAW format. ND filters come in different strengths measured in stops. The most popular for long exposures is arguably a 10-stop filter, although you can also buy less powerful filters or extremely strong NDs, such as 15 and 20-stops filters.
Ready to introduce magical movement to your images? Here’s the simply way to control time with a ND filter and capture a stunning landscape scene.
Here's how the scene looks without an ND filter. . .
Without a ND filter, the clouds are static and lack interest!
Step one
Use a tripod - With long exposures, it’s important to keep the camera steady or you’ll introduce blur into the scene. You can’t handhold the camera for this technique, so attach it to a tripod or, if you don’t have one, support the camera on a bench, or pile of flat rocks - anyway where it won’t move.
Lock off your camera on a tripod so it won't move during an exposure!
Step two
Focus up - If you add the filter straight away, the camera may struggle to establish focus. So, the solution is to focus up without the filter and, once you’re ready, switch to Manual focus (MF) by flicking the switch on the side of the lens, or via your camera’s Menu functions. This will stop the AF system hunting around and speed up operation.
Stop autofocus issues by switching to Manual Focus!
Step three
Work out your exposure - While you can use trial and error to work out the perfect exposure, there is an easier way that doesn’t involve any maths. With the camera in Aperture Priority mode (A or Av on the dial), set the aperture you wish to use (f/11 in our case) and then take a shot. If the exposure looks balanced, make a note of the shutter speed and then use one of many smartphone Apps available to enter the shutter speed and strength of ND filter. The app will then tell you what shutter speed to select once you’ve added the filter in front of the lens.
ND filter apps can be downloaded for free!
Step four
Add filter and change modes - Now you’ve got the right shutter speed dialled in, attach the filter holder and then slide in your ND filter, being careful to hold it at the edges so you don’t get finger marks on the glass. If your exposure is under 30 seconds, change to Manual mode (M), dial in the settings and take the shot.
Quality holders make it easy to quickly slide in your filter!
Step five
Use a remote cable - If your exposure is longer than 30 seconds, you will need to switch to Bulb mode (B on the dial), which allows the shutter to stay open for as long as you hold the shutter button down. However, physically pressing the shutter can lead to shake and blur in the frame, so a better solution is to use a remote release cable and trigger the shutter this way.
Using a remote is the best approach when shooting in Bulb mode!
Final image - Thanks to a ND filter, a long exposure has transformed the scene, capturing streaky clouds at the top of the frame!
Our exposure lasted six seconds and created amazing streaks!
. digitalrev.com2017-4-19 03:00
