The main types of filters used by professional photographers are called UV filters, polarizing filters and ND (neutral density) filters. Neutral density filters block light in varying amounts depending on the intensity of the filter. ND filter intensity ranges from ND2 to ND1000 and beyond (where ND2 reduces light in one step and ND1000 reduces light in 10 steps). Neutral density filters are mainly used for portrait and landscape work (with the strongest ND filters used in landscape photography).
Graduated Neutral Density Filters Are Practically Only Used by Landscape Photographers. They darken the sky during sunrise and sunset to balance the exposure of the sky relative to the foreground. While it is possible to replicate the effects of a graduated neutral density filter through HDR techniques, some photographers prefer to create their photos from a single image and often use GND filters in the field. On the one hand, a graduated neutral density filter allows you to do the capture in one go, which can be very satisfying.
And getting the shot in a single exposure certainly makes post-processing easier. Graduated color filters work the same as graduated neutral density filters, but instead of reducing light, they add color. In general, these filters are used to improve color in the sky. A popular filter for infrared photography is the Hoya R72 infrared filter.
Yes, many professional photographers use transparent filters in their lenses. And, basically, every professional landscape shooter works with a polarizer and some neutral density filters. These are the filters that often come as part of an additional package from the camera store when you buy your camera or lens. This is a piece of old technology that has long been obsolete, but remains alive, not least because it helps increase retailers' profit margins.
UV filters were originally used with film. The film is generally divided into different layers for red, blue and green. The blue layer was quite sensitive to ultraviolet light. However, even before digital cameras, most of the films that were produced had to overcome that problem to a large extent.
Today's digital cameras have eliminated it completely by using internal filters that block ultraviolet and infrared light. What does all this mean? It means that UV filters are completely useless when it comes to image quality. In fact, in many cases, with light sources inside the frame or slightly outside the frame, a UV filter can cause or increase lens flare. This is because there is an additional piece of glass in front of the camera for light to bounce off before being captured with the sensor.
Add to this the problem that less expensive (i.e. cheap) UV filters cause a decrease in sharpness and contrast, and why would anyone use one? The reason most people use a UV filter is to protect their lenses. But even this seems to be less useful than previously thought. A quick internet search on the effectiveness of UV filters in protecting lenses will show you evidence that a lens with a UV filter may not be more protected than one without it.
This has a lot to do with the fact that the front element of your lens is much stronger than you think and, in fact, stronger than the UV filter. Therefore, any force that can damage the lens, will most likely break through the UV filter with little resistance and damage the lens anyway. If you've ever owned “polarized sunglasses”, then you've experienced the effects of a circular polarizer. The lens filter type consists of two pieces of glass connected together and rotated independently to adjust the amount of polarization.
In practical use, simply look at the image in the viewfinder or on the screen and turn the polarizer until it looks the way you want it. A circular polarizer can be used for several things that can help your photo. Most importantly, the effects you can have on the image are difficult or impossible to recreate through software editing. By the way, they are not called circular polarizing filters because of their shape.
Refers to the polarization method that occurs. Older film cameras used “linear” polarization filters, but these prevented the use of light metering and some type of autofocus. So now they are outdated and rarely seen for sale. You should make sure that any polarizer you buy is a circular type, but it's unlikely that you'll find too many linear polarizers for sale.
What about those square pieces of glass that some landscape photographers can see using? They are also filters. Usually these are graduated ND and ND filters, but there are also square polarizers (although it may sound confusing since it is technically a square circular polarizer). Although it is more typical to have a standard polarizing filter in front of or behind the square filter holder so that it can be adjusted independently. A great starter combo is a circular polarizer and a 6-point ND filter.
It can give you those great landscape effects and still probably give you the benefits that a portrait photographer needs from an ND filter. If you slide a GND filter in front of the lens, you can darken the sky while keeping the foreground well exposed. Without a GND filter, you would have to take multiple exposures and merge them in post-processing to get a similar result. You see, a neutral density filter prevents light from hitting the camera sensor, giving you the freedom to open certain camera settings.
On the other hand, GND filters are expensive, and you'll often want to have at least a few (with different amounts of gradient, as well as some hard-edged and some soft-edged options). If you mount this filter holder to a polarizing filter, you could end up with vignetting even at 35 mm or more. Even with a filter, you'll need a camera that can work well with this filter attached, and some cameras are better than others. I have used a filter in almost all of my lenses since I started shooting more than a decade ago, and I have never noticed a drop in optical quality.
You can even stack ND filters to block more light, such as a 3-point filter and a 6-point filter to block 9-point light, but if you use circular filters, this can create a vignette that will need to be cropped out of the frame for the final image. If you use a hard-edge GND filter, the sky may get too dark and if you use a soft-edge GND filter, the sun will be overexposed. Now that you know the key camera filters on the market, you're probably tempted to run out and buy the cheapest filters you can find. I've never had any problems I could attribute to a filter, but I've been trying to resolve poor image quality when using my Tamron 150-600 G2 at 500-600 mm for a while now.
Personally, I prefer to keep a transparent filter on my lenses at all times, because they are easier to clean. There are many good owners of companies like Lee Filters, Cokin, Breakthrough Photography, and even a very inexpensive version of a company called The Filter Dude. . .
