Excellent guide, highly recommended for photographers to have a read. Contact the author if you require further information.
PTBPhotographyIs there supposed to be a link or a file? I can't see anything.5 months ago
Adminclick on FILTERS at the top of this page next to my name and then click on the TAB that says PAGE DETAILS.... or a quick way by using this link -...click on FILTERS at the top of this page next to my name and then click on the TAB that says PAGE DETAILS.... or a quick way by using this link - photographersandmodels.com/pages/viewpage/7-filter…Show more
All photography is all about capturing the quality and intensity of light. Filters are used to modify the light before it enters the lens to improve or change the image. Filters are sheets of glass or plastic that go in front of the camera lens to serve different purposes. They are really useful for capturing scenery in difficult lighting conditions or can be used to enhance colours, reduce reflections and protect lenses.
Some of the tools in post processing software can simulate filters, but some cannot and some actually help in getting better results during post processing. hat are Filters, and
Why Should You Use Them?
Sunglasses are used help see better in intense light, protect eyes from UV rays and reduce glare. Filters serve similar purposes, can reduce reflections, protect against damage, partly or fully reduce the the light entering the lens and enhance colours.
Filters can actually harm images if not used properly. It is necessary to know not only what filter to use but when and how to use it. There are loads of filters available from cheap UV filters through to very expensive ones costing several hundred pounds. It can make choosing the right filter for what you want to do quite difficult.
Lens Filter Systems There are three main lens filter systems: Circular screw-on filters that mount directly on the lens thread. These can be UV, clear, circular polarizing, neutral density or colour filters. They come in different sizes to fit lenses. Square filters are good for landscape and other other outdoor photography. A holder fits directly to the lens thread to take the filter. Most popular are 3×3 and 4×4 inches. Filters can be stacked together but this can add reflections and reduce the quality of the image. Oblong filters are used mainly for landscape photography. They are mounted like square filters with a filter holder system. Oblong filters are the choice for landscape photography as circular filters are impractical for graduated neutral density filtering (of which more later). Most popular size is 4×6 inches but larger and smaller ones are available.
Types of Lens Filters
UV (Ultra Violet) and Clear These are used simply to protect the lens. It is cheaper to replace a filter than to try to repair a scratched or broken lens element. Keep a clear filter on lenses as they are easier to clean. Avoid cheap filters as they can affect the image quality. Polarizing Filter Circular polarizers are just like polarised sun glasses, they cut out glare and reflections. Circular polarizing filters have two elements, the front element rotates and the fixed rear element polarizes the light. When the the two elements are aligned and the camera is at the optimum angle to the sun, the image should have brighter colours, bluer skies and fewer reflections, especially off water. They can also reduce haze when shooting landscapes. The maximum effect of polarization is found when the lens is pointed at right angles to the sun. A good rule is to have the sun on your left or right shoulder when shooting.
Beware as there may be a loss of approximately 1 to 2 stops when using polarizing filters.
Neutral Density (ND) Filter The neutral density filter is used to reduce the amount of light that gets into the camera. The effect is to reduce shutter speed and increase the time of the exposure. This is particularly useful in daytime when there is a great deal of light that can't be decreased by stopping down the aperture and or decreasing ISO. This is particularly useful when shooting waterfalls or moving water like the sea to get the “silky” look on the water. Neutral Density filters come in a variety of densities from ND2, the least dense, up to ND10, the most dense, where the number refers to the number of stops of light entering the lens of the camera. To get the “silky” look on running water set the camera on a slow shutter speed and a wide aperture and use an ND6 or 8 filter to effectively increase the exposure time by reducing the light entering the camera. Experiment to find what works. Use an ND2 filter to increase contrast and brightness on really bright days.
Neutral density filters can be both circular and rectangular. With circular filters one for each size lens and density will be required and the use of step up/down rings should be avoided as they can cause vignetting.
Graduated Neutral Density (GND) Filters and Filter Holders
The difference between neutral density and graduated neutral density filters is that the GND is half clear. GND filters are made in a rectangular shape and must be used with a filter holder or be held by hand in front of the lens. Using a filter holder means that multiple filters can be stacked, rotated and moved up and down easily. The disadvantage of a filter holder is that it can add vignetting when using a wide-angle lens.
Hard-Edge GND Filter Hard-edge GND filters can be used where the sky is bright compared to the foreground and the transition fairly flat as in a seascape. The hard edge of the filter is lined up with the horizon and the sky is then darkened. A GND2 or perhaps 4 is usually enough to balance the image. When the horizon is not flat then a soft edge GND filter is used.
Soft-Edge (GND) Filter
As the name implies, soft-edge GND filters gradually change from dark to clear and are used when photographing the horizon when it is not flat. Mountains, hills etc. can be difficult for hard-edge GND filters and a soft-edge GND filter works much better due to the gradual transition. Use soft-edge GND filters for landscape photography. Colour Filters Colour filters are used to alter the white balance of the camera. They are used to either correct the white balance or for absorbing a particular colour allowing other colours to dominate the image. However, all this can be achieved more easily in post processing software.
Special Effects Filters
Special effects filters can produce some interesting effects, but most can be easily produced in post processing software. The star filter can be easily created in a couple of steps using “Motion Blur” and a softening glow can also be easily created with “Gaussian Blur”, most other filters can also be created during post processing.
Filter Material, Glass or Resin Filters?
Filters are made from many different materials. They can be glass, plastic, resin, polyester or polycarbonate. Glass filters are usually the highest quality, but can be very expensive and are easily broken, especially the square or rectangular ones which can tend to be heavy. Plastic or resin filters are considerably less expensive than glass and are not easily broken. They are also lighter and a good choice for square or oblong GND filters. Polyester filters are thinner and lighter than glass or resin and can be very high quality, but scratch easily and therefore not very practical in the field. Polycarbonate filters are very tough and scratch-resistant and are a good alternative for use in the field. Non-glass filters are a good, inexpensive choice for beginners for learning, practising and experimenting, however, for the best results, when able and budget allows, glass is the best choice.
Conclusion
There is a huge choice of lens filters, all giving different effects. Where to start? 1. A UV or clear filter to protect the lens. 2. A polarising filter to cut down glare. 3. For the landscape photographer, square or oblong GND filters and filter holder. That could well be all that is needed. Use step up rings, not step down as they cause vignetting, to minimise the number of filters needed for different size lenses. If you have any questions please email me and I will do my best to answer them and any comments will be welcome.
CirroCu
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Filters
A Beginners Guide to Lens FiltersAll photography is all about capturing the quality and intensity of light. Filters are used to modify the light before…