Friday, 5 June 2015

Long Exposures - Using 9 & 10 stop ND Filters

Hoya ND400 2.7 (9 stops)
The Neutral Density filter is a very handy filter to have in your camera bag. Although it doesn't get used that often in our Travel Photography it certainly should be near the top of your list of "must have" creative filters.

What is a ND 2.7  & ND 3.0 Neutral Density Filter?

B+W ND110 3.0 (10 stops)
Both of these filters have the same purpose except the ND 2.7 reduces about 9 stops of light from reaching your sensor/film and the ND 3.0 reduces about 10 stops of light. To calculate the reduction of light of any Neutral Density Filter simply divide number by 3 e.g. ND 2.7 / 3 is 9 stops. We essentially use these filters to create a smooth water effect in an image to give it mood and emotion although it also has other benefits. 

In the middle of the day you will sometimes find that the light levels when shooting are too bright to allow you to shoot at slow shutter speeds even when stopped down to the smallest aperture (usually F22) and the ISO is set to its lowest (usually 50 or 100). Although the shutter speed will be reduced dramatically it usually will not be enough to get the effect you want especially when shooting the following -
  1. Waterfalls - where you want that dreamy blur look of the water cascading over the waterfall.
  2. Seascapes - to create the misty look and soft flat look in seascape shots.
  3. Clouds - for images that you want blurred/streaky clouds.
  4. Reduce the visibility of moving objects. For example, removing people from shots in busy thoroughfares. 
There are quite a few brands on the market but beware as you can get some weird effects with some brands and therefore we recommend that you stick with the well known brands such as Hoya, B+W, Tiffen, Formatt-HiTech, Singh Ray and Lee. We have not noticed any colour cast on images taken with the ND400 filter however the B+W ND110 does have a slight red colour cast but this is easily corrected in post processing. 

The filters are also generally quite expensive so make sure that you keep it clean and scratch free. Make sure you keep it in it's original plastic container or in a soft filter holder. Also note that with the increased exposure time, every spec of dust on your sensor is amplified so you may need to do a bit of cleaning of the image in your post-processing.

This was taken in the Bay of Fires Conservation Area. As soon as we saw this image we knew it would be great using the ND400 filter (9 stop). We took several images as the water wasn't always extending as far into the foreground as we wanted. In Photoshop we simply opened the images we wanted to use as layers and using masks we painted through the water in the foreground to give it more blur and making it a better image.


We have released an E-book which includes a step-by-step guide to using these filters for long exposures and a handy printable pocket guide to using the filters.
We hope you found this post useful and we would love to hear any comments from you. 


No comments:

Post a Comment

Hope you enjoyed this post. Leave us a comment and subscribe with your email address to receive new posts.