A neutral density filter is a filter that attaches to your lens and reduces the amount of light hitting the sensor (“film”). You will need to increase exposure, change aperture or boost ISO to allow additional light into the camera in order to produce a normal, acceptable exposure. In this post we’re discussing a 10-Stop Solid Neutral Density Filter. This means you have to give 10x more exposure than what you normally would need to in order for your photo to be correctly exposed. With such a long exposure, moving objects like clouds or water will blur to a mirror-like texture. People will disappear entirely if they are walking around.
Why Use a Neutral Density Filter?
The usual goal is to blur water or the sky or other moving objects. With long exposures, moving objects like clouds or water will blur to a mirror-like texture. People will disappear entirely if they are walking around.
The picture here was made at mid-morning on a sunny day and included a pond which is still except for wind, ducks and geese landing and swimming and an aerator running at the far end of it. The exposure was eventually made for 25 seconds, allowing the pond to be rendered almost like a mirror as there was a slight breeze blowing the water.
Here are the steps:
- Mount the camera on a tripod
- Compose the picture and focus your lens. If you are using autofocus, turn it off after focusing. The 10-Stop Solid Neutral Density Filter is so dark, autofocus won’t work with the filter on your lens (step 5 below). Neither will you be able to see to manually focus once the filter is on, so focus now and be careful not to change the focus during the next steps.
- Take a test shot and note the correct exposure time without the 10-stop filter on the lens
- Multiply the exposure by 10
- Carefully screw on the 10-Stop Solid Neutral Density Filter or place it in its holder
- Make your estimated long exposure
- Review to see if the exposure is usable. If not, try again. It will take a few tries to get it right.
Other examples of photographing using a 10-Stop Solid Neutral Density Filter via a Google search.