Why should you get a grey filter?
A grey filter offers the additional possibility of controlling the light hitting the sensor, in addition to the values for ISO, shutter speed and aperture. Especially in landscape photography, it is an advantage not to be limited to these three parameters, as ND filters allow you to adjust the exposure time according to your own creative ideas. The settings for aperture, shutter speed and ISO can only be used within a narrow range in landscape photography, as you are often limited for the desired shot:
You want to set this value to the nominal value because the sensor has the highest performance at this setting. This is where the camera has the highest dynamic range, and also the lowest image noise. You should not vary more than 1-2 steps from the nominal value, and preferably downwards.
The aperture should also define the depth of field and the quality of the image. There is a very narrow range in which the lens has the highest sharpness. In addition, the aperture also affects the depth of field. The aim is to ensure that the entire field of view is in focus in most situations. Here, too, there is a margin of 1-2 f-stops. Nevertheless, a reasonable range is between approx. f/7.1 and f/14.
After the values for ISO and aperture have been defined, the shutter speed now remains. So if you want to expose the photo appropriately, you have to select the correct value that, together with the previous criteria, will give a balanced exposure. This severely restricts creativity. Photography is creativity and not pure execution. Therefore, you need a suitable tool to be able to influence the incident light and, moreover, to have a possibility to choose the shutter speed at will. This tool is the ND filter.
What does a grey filter do?
A grey filter is used to take long exposures in daylight. Since a picture taken in daylight would be completely overexposed, i.e. actually burnt out, at an exposure time of about one second, you take a picture with an ND filter. These filters are uniformly darkened and thus reduce the amount of light reaching the sensor. This means that the exposure time can be extended despite a bright environment.
Our grey filters are available in different strengths. 8x, 64x and 1000x. The names are almost self-explanatory: with an ND1000 you can expose 1000x longer than would be possible without a grey filter.
What effects can be achieved with a grey filter?
Possible applications of a grey filter are for example the following:
Motion blur - blurring clouds or making flowing water velvety soft to the touch
Eliminating moving people or vehicles - This can be very useful on holiday, for example, when a popular sight is repeatedly overrun by tourists.
Preventing overexposure - In some situations, such as on a sunny day at the beach, the light may be too bright and despite using the smallest aperture and fastest shutter speed, the photo would simply appear overexposed. To avoid this, ND filters with a low filter factor are perfect.
The right exposure time with a grey filter
As mentioned earlier, the strength of the grey filter is related to the length of the exposure time. So with an ND8 filter, the exposure would be 8 times longer. For example, if the camera specifies 1/20 second as the correct exposure time, this becomes 50 seconds exposure when using an ND1000 grey filter.
It is also easy to use the aperture priority mode. You set the aperture yourself and the camera automatically calculates the appropriate exposure time. In most cases, modern cameras produce a very good result. For an architectural or landscape photo, you should usually use an aperture value between 9 and 11 in order to achieve the greatest possible depth of field.
If you want to take photos with an ND filter, you have to be able to set the shutter speed, ISO and aperture. This means that you should shoot in "M" mode, i.e. manual mode.
Do I need a tripod to photograph with a grey filter?
Generally you need a tripod, unless you are using the filter to take a portrait at an aperture of 1.4 and in the midday sun. In most cases, ND filters are used to achieve longer exposure times. The rule of thumb is that a maximum of 1/focal length can still be photographed handheld. When using grey filters for long exposures, exposure times between one and thirty seconds are usually used. For this you definitely need a tripod, otherwise the picture will be blurred.
Procedure for taking the picture
- Set up the camera, lens and tripod.
- Set the desired frame, focal length and aperture.
- Focus manually.
- Then let the camera determine the exposure time using the aperture priority mode.
- Set the camera to manual mode (M).
- Screw/attach the ND filter to the lens.
- Now you can determine the new exposure time based on the grey filter used and the correction table shown below.
- Release the shutter using the remote shutter release.
Do I need a specific ND filter for different cameras (Sony, Cannon, Nikon, etc.)?
No, it does not matter which camera manufacturer you use. You can use all ND filters available from us on all cameras as long as the filter diameter fits the lens used.