These are sometimes also called "split filters. Prior to digital cameras, GND filters were absolutely essential for capturing dramatically-lit landscapes. With digital cameras one can instead often take two separate exposures and blend these using a linear gradient in photoshop.
On the other hand, this technique is not possible for fast moving subject matter or changing light unless it is a single exposure developed twice from the RAW file format , but this increases image noise. GND filters come in many varieties. The first important setting is how quickly the filter blends from light to dark , which is usually termed "soft edge" or "hard edge" for gradual and more abrupt blends, respectively. These are chosen based on how quickly the light changes across the scene, where a sharp division between dark land and bright sky would necessitate a harder edge GND filter, for example.
Alternatively, the blend can instead be radial to either add or remove light fall-off at the lens's edges vignetting. Placing the blend should be performed very carefully and usually requires a tripod. The soft edge is generally more flexible and forgiving of misplacement. On the other hand, a soft edge may produce excessive darkening or brightening near where the blend occurs if the scene's light transitions faster than the filter.
One should also be aware that vertical objects extending across the blend may appear unrealistically dark. Note how the rock columns become nearly black at their top compared to below the blend; this effect is often unavoidable when using GND filters.
A problem with the soft and hard edge terminology is that it is not standardized from one brand to another. One company's "soft edge" can sometimes be nearly as abrupt a blend as another company's so called "hard edge". It is therefore best to take these on a case by case basis and actually look at the filter itself to judge the blend type.
Most manufacturers will show an example of the blend on their own websites. The second important setting is the differential between how much light is let in at one side of the blend versus the other the top versus bottom in the examples directly above. This differential is expressed using the same terminology as used for ND filters in the previous section.
Similarly, a 0. Most landscape photos need no more than a f-stop blend. Nowadays UV filters are primarily used to protect the front element of a camera lens since they are clear and do not noticably affect the image. With film cameras, UV filters reduce haze and improve contrast by minimizing the amount of ultraviolet UV light that reaches the film.
The problem with UV light is that it is not visible to the human eye, but is often uniformly distributed on a hazy day; UV therefore adversely affects the camera's exposure by reducing contrast. This was originally designed to reduce the slightly blue cast of color film, but with digital cameras this isn't really an issue. Even though this filter will prevent the worst of the dust, dirt and water reaching the front of the lens, you may still need to clean the filter to prevent this dirt affecting your images.
For dust and dirt it's best to use a brush or air blower to remove this without damaging the filter. If you try to wipe the filter clean there's a risk that you'll scratch the surface. Wiping the filter to remove water drops needs to be done extremely carefully, as it's likely that there will also be some dirt or dust that can become embedded in the cloth or tissue, and scratch the filter.
Because they are primarily for keeping attached to your lens for protecting the front element, round, screw-in skylight or UV filters are the best option. When it comes to a camera lens filter guide, look no further than this article. There are variations of these camera accessories, such as a graduated ND filter , but these are the key filter that you would want to use.
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Need more info? See how it all works here. But then, why would we want a UV lens filter? In actuality, this is a problem that affects film shooters, and rarely digital shooters. Digital sensors are much less sensitive to UV light. Why still use one? Well, I never take mine off the camera.
This photography filter will protect the front element of my lens. So, if I accidentally knock it, my lens filter gets damaged, and not my rather expensive lens. Some people seem to think camera filters reduce the image quality. If you have an expensive, professional lens, like telephoto lenses or a high end wide-angle lenses, which you would like protected — use a UV lens filter.
For safety, there are no better DSLR lens filters out there. Keep in mind though, that poor quality UV filters are a common cause of lens flare. Polarizing filters are really useful, because they reduce glare, and improve the saturation of photos. In fact, plenty of landscape photographers argue that you should never leave home without a polarizer. And polarizers enhance skies, too; pop a polarizer on the front of your lens, and the sky will suddenly become the deepest blue.
This is a trick that some street photographers and portrait photographers use to come up with some very cool, through-the-window type shots. Now, a polarizer does come with some drawbacks. For one, modern polarizers reduce the light transmitted through your lens.
But for landscape photographers, architectural photographers, and cityscape photographers — who often deal with light reflecting off water and light reflecting off windows, respectively — a polarizer is a must.
But why would you want to darken your lens? You see, a neutral density filter blocks light from hitting the camera sensor, which gives you the freedom to open up certain camera settings. But what if you want to use a long shutter speed to create silky waterfalls?
Or streaking clouds? Landscape photographers use neutral density filters all the time, especially when shooting water or dramatic skies.
So they put an ND filter over the lens, which blocks light and allows them to shoot at whatever aperture they please. A 3-stop ND filter lets you increase your shutter speed or widen your aperture by three stops of light, whereas a stop ND filter is far stronger, and gives you ten stops to work with. Neutral density filters are very useful — but they can also be frustrating to work with. So you often have to focus manually in advance, then screw on the ND filter, before taking your shot.
Many anti-filter folks also question whether a filter will truly protect your lens in most situations. Graduated neutral density filters are designed to darken only part of the image — generally the top half, though you can purchase reverse graduated neutral density filters that are darkest toward the middle and get lighter as you move upward.
And this will cause your camera to either blow out the sky or underexpose the foreground unless you take certain steps to compensate. If you slide a GND filter in front of the lens, you can darken the sky while keeping the foreground well-exposed. Hard graduated neutral density filters have a very rapid transition.
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