The filters are accessories that are attached to the front of the lens so that we can obtain a series of photographic effects, such as the silk effect of water or a more bluish sky.
In this article we will try to see all the types of photographic filters that exist today and what they are for. I will begin explaining the different types and then we will see the different ways that there is to couple it in front of our objective with its advantages and disadvantages.
The different types of filters
This type of filters are basically to protect the lens. Imagine that you are photographing a beautiful sunset with your expensive lens attached to the camera and a gust of wind knocks the camera against the ground. In these cases there are many chances that the objective will break, however, if you wear an ultraviolet filter, the only thing that will be broken will be this and you will save the objective.
The advantage of this type of filter is that it is very cheap, so it is usually used as a protector.
Another characteristic of this type of filters is that they serve to remove contrast, although it is practically imperceptible to the naked eye.
Removing this last the effects that can occur in photography are minimal.
This is one of the most used filters by all types of photographers. Basically this filter serves two purposes. On the one hand it enhances the blue color of the sky and on the other it eliminates the reflections on surfaces of metal, water or crystals.
Imagine that you are taking a picture of your brand-new car, to ensure that nothing is reflected in the metal you must use one of these filters.
Neutral density filter
This is one of my favorite filters, it serves to reduce the amount of light that enters the lens and therefore allows us to take pictures with a higher shutter speed.
The neutral density filter can be used to achieve the silk effect of water in rivers, waterfalls, seas, etc. Another effect of the long exposure are clouds. Finally, this type of filters can also be used, and this is something that not all amateur photographers have thought, to eliminate people when we are photographing in a place where people usually spend. To achieve this, the shutter speed must be very low.
Gradient filters are filters that serve to apply the effect to a certain part of the photograph.
For example, the most common filters of this type are those of neutral density that only affect the upper part of the photograph. This type of filters are widely used by landscape photographers, who in view of the great difference in light between the sky and the earth (for example at dawn) use this type of filter to compensate for the exposure.
Imagine that you are in a beautiful sunrise by the sea and you are going to take a photograph where your center of interest are some rocks that you have right in front of you. In this case, the amount of light in the sky is much higher than that of the rocks, and they will be photographed with a backlight, which makes it even harder to take if you do not want them to appear very dark. In this case a degraded filter will come from pearls, because we can reduce the amount of light that enters the target from the sky and leave the bottom of the photograph as is, and as a result we will have a photograph with no burned parts in the sky or too much dark in the rocks.
I love the effect that occurs with this type of filter. What is achieved by incorporating it into your goal is to block the infrared wavelengths, achieving really beautiful and surreal landscapes.
The most characteristic of the effects we can achieve is to transform the green color by white and achieve a much more intense blue in the sky.
The only problem with this type of filter is that we must learn to edit this type of photos in photoshop or another photo editing program, because when we make the shot the result we will see is a photograph with an intense red color.
For the use of this filter we will need a tripod because the exposure times are very long.
These filters are used so that a kind of star appears in the lights of the light bulbs. It is very good when we take an urban photograph where the lighting of the streets is on.
We must bear in mind that this effect can also be achieved with very small openings of the diaphragm, but there may be times where we can not do so and we should resort to this type of filter.
This is a type of filter very little known in photography. It has the same effect as the neutral density filter, but it is located at the back of the lens. It is used mostly in wide angle lenses, since the lens is very curved and it is impossible to put a thread to put a filter in the front.
Retro effect filter
If you like instagram filters this type of filter you will love it. What it does is give a vintage effect to our photography. I have never used any, it is also something that can be easily done in photoshop, but I do not discard it out of curiosity I will buy some in the future.
Although it was used mostly in analog photography nowadays it is not often used too much. It is a type of filter that what it does is enhance a certain color of the photograph. There are blue ones (for the sky), green ones (trees), yellows, reds, etc.
How to fit it to our goal
These filters are round and curl to the front of our lens. They are very comfortable to use and also as I said before they serve to protect the crystals of our lens.
When we buy a thread filter we must take into account that the diameter of this matches our objective, so before buying it we will look at the characteristics of our lens and buy the thread filter that fits. The larger the diameter, the more expensive it will come out.
Unlike thread filters these have three pieces. On the one hand we have the ring that normally goes screwed to the lens, so just like the thread filters we should look at the diameter. Then we have the filter holder, which depending on the size of the filter that we will buy will have one size or another. Finally we have the filter itself, which is a kind of cardboard that is put in the filter holder in front of the lens.
What do I buy?
Well that depends on each one, I for example the neutral density filter I have it of thread, but the gradient I use filter holder. The advantage of the latter is that you can dock it as you want in front of your objective, with the advantage that you can move the horizon line where you want. If you buy a screw you will have to leave the horizon always in the center of the photograph.
The digital filters have nothing to do with the subject we are dealing with, anyway I mention it so that you have it clear. If you want to make a certain effect in a photo, it is usually more advisable to use filters than to make the changes later in the process.
These filters are very common in instagram, and there are also many plugins in photoshop that generate effects of different types.
Tips if you are going to use a photographic filter
One of the most important things you should keep in mind if you are going to buy a photographic filter is that you do not skimp on expenses, as practically always in photography.
A filter always subtracts some clarity from the photograph we are going to make. If we use very cheap filters that quality loss may be very important and practically ruin the photo, so it is important to spend money on these types of filters, even if you are using a good computer.