by Dr. Robert Berdan
November 11, 2012

West Coast Island in the fog - Filter Forge edge effect and sepia tone gives this image an aged effect.
In the past photographers often used glass filters attached to their lens to modify their photographs. Black and white photographers would add yellow, red or green filters to modify certain tones in their photographs. A red filter would make anything in the picture that was red lighter in tone and complimentary colours like a blue sky much darker in tone. Today if you want a black and white image it's better to photograph in colour with your digital camera and then convert the image into Black and white, or sepia in Photoshop or similar image editor. Using the black and white filter you can control all of the tones in your image. Converting an image to black and white is just one of hundreds of different filter effects you can apply to your images during post processing in Adobe Photoshop. Below are some examples of just a few of the digital filters that you can apply with Photoshop or through other company's digital plugins or filters.

Filter Forge plugin for Adobe Photoshop - BW and grunge edge effect. Waterfall as Spring Hills Provincial Park.
I am often asked what filters do you recommend using with digital cameras - the good news is you only need a couple. The first is a circular polarizer for your wide angle lens, a 2-stop graduated neutral density filter in both the hard edge and soft edge variety. Grad filters are used to darken the sky and lighten the foreground, especially at sunrise and sunset. If you shoot RAW files it's easy to add a grad filter afterwards in Adobe Camera RAW. You can also add grad filter effects using layers and the overlay blend mode if you work with JPG images, but its still best to use grad filters while you shoot if possible.
Clear glass, Skylight, or UV filters are often recommended when you buy a new camera to protect the lens. I prefer to use a lens hood to protect the front of my lens and the only time I put a UV filter on is to protect the lens from ocean spray when kayaking and sometimes if I am in a sandy place and there is a strong wind. Otherwise, A UV filter degrades the image quality slightly, creates another interface to reflect light off of. My advice is to avoid UV filters if you want the sharpest highest quality images. If you can't see the difference you are welcome to ignore my advice, but I am as stickler for quality.

An array of filters, most of which are no longer needed, the exception is a circular polarizer and sometimes a graduated neutral density filter. The Blue\Gold polarizer was popular for a while and it can sometimes add impact but I rarely use it anymore.
I also no longer use any kind of coloured filters e.g. 81B warming filter or cooling filters as I can create any kind of colour cast I like in Adobe Photoshop easier, faster and with much greater control.

Above is a 0.6 ND (2 -f/stop) soft graduated filter and a hard edge graduated filter. The third is a soft edge coloured grad filter. All of these filters can be simulated in Adobe Photoshop (see my on-line tutorials) even the coloured grads. I still use the first two types of filters in the field, but when I don't have them I use Adobe Photoshop adobe camera raw to add them. Lee and Singh Ray make acrylic grad filters for around $150 each - both of them scratch easily and I found I had to replace them about every 18 months. Tiffen makes glass grad filters that are about $300 each, but they don't scratch easily, have higher optical quality with fewer reflections and are also widely used in the movie industry - see links below for more information.

Computer software can simulate most types of optical filters that you attach to your camera including those that blur, soften or alter your images in multiples ways. In the past I have experimented with putting different types of glass in front of my lens e.g. thick glass from a coke bottle, UV filter covered with Vaseline, or a stocking held in front of the camera lens to mention just a few. Today its possible to experiment with thousands of possible filter effects after capturing the images. If you are the type of photographer that only shoots documentary type images then you can stop reading right now - using filters is about additional control and manipulation. On the other hand if you are open to experimentation and to "artistic interpretation" then there are a thousands of digital filter effects you can apply to your images. Some digital filters will sharpen your images, others can blur them or even make them resemble paintings.
Some filter effects only modify the edge of your photographs - all you have to do is be willing to play and experiment. If you own Photoshop, any version check out the digital filters. You can also purchase plug-ins e.g. Filter Forge or Nikk filters. On September 17, 2012 Nikk was purchased by Google, whether that means they will offer some of the filters for free or not waits to be seen. Applying filters with your computer and software is quick and easy and some filters offer numerous sliders and options. Some filters simply make apply various photo adjustments easier and faster though most filter effects can be created manually in Photoshop by experienced users. If you have the time and interest learning Adobe Photoshop is one of the best things you can do to control and manipulate your images to appear the way you want them to. Keep in mind, that no filter is going to make a bad photo into a good photo, however sometimes adding filters to "straight" images can make them much more interesting and sometimes even elevate them to "art". One photographer that excels at adding digital filters, is Dan Burkholder. Dan takes image with his Iphone and then applies filters using apps that he downloads. Check out his web site to see examples.

Filter Forge - LOMO Filter. LOMO stands for Leningrad Optical Mechanical Amalgamation a company that produced cheap plastic cameras though it also produced high quality optics for the military. LOMO photographs are often associated with weird colours and experimental photography. It's not for everyone, but it can be fun to play with.

Here is a straight image with some minor adjustment of colour saturation of a party of baby foxes.

This is the same image after applying Filter Forge Plug-in - HDR painting filter. The photo takes on the appearance of an illustration that could be used in a book - it just has a different feel to it.
No filter works best with all images. The only way to know if a filter effect can enhance or alter the feel of an image is to experiment. The good news is that Photoshop has hundreds of filters already built in. Other companies like Filter Forge offer you the chance of downloading their filters and testing them for free for 30 days. The possibilities are endless.

Adobe Photoshop filters offers a wide variety of effects that can be applied to your photos and you can apply more then one filter.

Straight image taken on an overcast winter day of a small pond in Bowmount Park near my home

Adobe Photoshop Dry Brush filter applied to this winter scene I took in Bowmount Park near my home.

Adobe Photoshop Graphic Pen filter applied to the picture.

Photo after applying Adobe Photoshop's Oil painting filter.

Above is Filter Forge 3.0 plugin for Photoshop - you can download and try their filters free for 30 days.

Grunge filter with a cloth like texture applied over top of this image - Bullrushes at Vermilion Lake

Photo above uses a Photoshop action to create star trails.

Here is the same photograph after apply Filter Forge distorsion filter - this may be too abstract for some, but others will see there are no boundaries when it comes to playing with your images.

Filter Forge Grunge and edge effect

My father standing next to Alexandra Falls in the NWT with Filter Forge Paint effect

Grain elevator in Searle, AB with grunge filter and edge effect from Filter Forge

Alberta marsh covered with fresh snow - Photoshop's Dry Brush filter applied.
Digital filters are fun to play with especially over the winter time when you might not feel like going outside, or after work in the winter when its dark outside. The possibilities are endless. Keep in mind sometimes photo filters just don't add anything or result in a better looking photo you have to decide what works for your. Sometimes a photograph looks best without any kind of filter, but most of us that have been in the business of photography realize that sometime certain photographs just don't have enough impact on their own and sometimes a filter or edge effect can make an image commercially viable. If you don't mind working on your images with a computer you might try some of Photoshop's filters and if you get hooked you can try some of the other digital filters that are available. RB