Grey graduated filter
As the name of the filter suggests, a graduated grey filter (GND filter) does not reduce the incoming light over the entire surface. On the one hand, this type of filter has a specified strength (e.g. ND8 to ND32), on the other hand it is made of clear glass and does not influence the exposure. Between these two sides there is a gradient from clear glass to grey filter, this gradient varies depending on the design of the filter.
GND filters are used to compensate for the strongly varying brightnesses of a motif. This occurs primarily when one part of the motif is very dark, while another area is very bright. This is especially common in landscape or architectural photography. A large part of the motif that is very bright compared to the rest of the picture is the sky with its clouds. To prevent the sky from looking burnt out or the landscape from appearing too dark in the shot, a grey graduated filter is used to balance out the differences in brightness.
Basically, you will find the same information in the designation of the strength of a grey gradient filter as in the case of a grey filter. With GND filters, however, the range is much smaller. Something above the ND32 filter does not really make sense anymore for a grey gradient, because the differences in brightness become too big.
Which graduated filters does Kase offer?
In general, the use of a filter system controls and influences the incident light including the colour spectrum. Grey graduated filters play a particularly important role in landscape photography. This is because this type of filter makes it easy to adjust the usually strong difference in brightness from the sky to the actual foreground or subject of the picture. Depending on the situation, we therefore offer you grey graduated filters in different strengths, also called densities.
- GND 0.6 - 2 f-stops
- GND 0.75 - 2.5 f-stops
- GND 0.9 - 3 f-stops
- GND 1.2 - 4 f-stops
- GND 1.5 - 5 f-stops
These values indicate by how many f-stops the dark area of such a filter reduces the incident light. In addition, the filter's gradient from clear to grey is indicated. A distinction is made between the following five variants:
The soft, medium and hard GND filters are the most common variants. These have their darkest area at the top edge and become lighter towards the bottom. When which type should be used for photography is explained in the next section.
How do the different GND filters differ and when should they be used?
Soft GND filters
These filters have a very soft transition from clear to darkened. This makes them suitable for scenes that have a very wide or interrupted transition from the sky to the actual foreground. An example of such a scene is a mountain landscape that crosses the horizon line. The rock formation in the sea that you encounter during your holiday is also predestined to be photographed with the help of a soft GND filter.
Medium GND filters
Our Medium GND filters are similar to the Soft GND filters, but the gradient is not quite as smooth. These filters are the most versatile and can be used for most situations, for example to photograph away from the sun or against the sun.
Hard GND filters
These types of GND filters have a hard gradient from clear to grey. Therefore, they are suitable for scenes that show a clearly visible transition from the sky to the actual foreground. This type of filter is most useful when shooting landscapes where no element extends above the horizon, an example of this is when shooting the sea with a wide view of the ocean. In addition, these filters are used when a hard transition against the sun is needed.
Reverse GND filter
Reverse GND filters with a "reverse gradient" are similar to GND filters with a hard gradient except for the fact that the darkest part of the filter is not quite at the top of the filter but is slightly shifted down towards the centre. These filters are intended for shots taken against a light source and where the light is strongest at the horizon.
Centre GND filter
Centre GND filters have the darkest area in the centre of the filter. Towards the top and bottom there is a transition to clear glass. These filters are used when photographs are to be taken against a light source. This is of great advantage for sunrises and sunsets, for example.
Do I have to pay attention to anything when buying grey graduation filters if I own a Canon and a Nikon camera?
No, when buying filters, the brand of the camera is not decisive. This is because GND filters can be used independently of the photographer's camera brand and can therefore be used with any manufacturer. Only the diameter of the lenses used is decisive when buying. However, adapter rings can also be used to achieve a high degree of flexibility.
What is the difference between graduated grey filters and other graduated filters?
As the name suggests, both are graduated filters. Grey graduated filters are grey to clear. However, there are also filters that run from one colour to clear. In the 80s, for example, the tobacco graduated filter from Cokin was very popular. Nowadays, however, coloured graduated filters are hardly ever used, as this effect can be recreated on the computer with little effort.
Why do I need a graduated filter?
GND filters are used to darken the lighter part of a photo, often the sky, in a colour-neutral way to adjust the exposure of the image. This allows the camera to capture the dynamic range of an image more fully. The camera gets an extension of its capabilities, so to speak, by using a GND filter.
There are also other tools, for example in post-processing, to compensate for the differences between light and dark areas in a photo. Nevertheless, in our opinion, graduated filters cannot be completely replaced by post-processing in landscape photography.
What makes square graduated grey filters so practical?
Almost all of the filters presented in this article are also available in round versions for screwing or plugging on. However, a quick and frequent filter change with screw-on filters is not quite as easy. They are often screwed on too tightly and are difficult to unscrew again. Sometimes the focus of the camera or, in the case of zoom lenses, even the previously painstakingly selected image section can become misaligned. Changing or removing rectangular filters is quicker and easier because the filters are simply inserted into a filter holder. With a little practice, this can be done without changing the focus or framing the picture, as long as the camera is on a tripod. Most photographers prefer to use graduated filters together with a filter holder and thus change the filters quickly and conveniently.
With screw-on filters, the actual filter is embedded in a ring, which can then be used to screw it onto the lens. This means that the dividing line between light and grey is usually fixed in the middle and the possibilities for image composition are thus very limited.
As described before, the angular grey graduated filters are pushed into a filter holder. One quickly notices that these filters are often not square, but rectangular. This shape allows you to slide the graduated filter up or down inside the holder. This gives you full control over where the grey gradient starts and how much of the image is affected by the grey gradient. This means that the filter can be adapted to the desired image composition and can be shifted precisely according to the position of the horizon. Unfortunately, this is not possible with graduated filters for screwing.