An Introduction to Photographic Filters

Filters are great tools for photographers. There are a lot of different filters, each with different effects. Some are quite dramatic and other are more subtle, but no less crucial to creating great photography. To name a few uses of filters:
Correction Filters – to create a photograph as you see it
Contrast Filters – to create a photograph as you imagine it
Neutral Density Filters – to reduce the amount of light entering your lens
Light Balancing Filters – to correct color shifts
and more . . .

Are filters still necessary, in the world of digital photography?
Absolutely! Some filter effects can be created through the settings of your digital camera, instead of attaching a filter to the end of your lens. Whether filtering in camera or with a screw on filter, it’s necessary to understand what they do so they can be used effectively. There are filter effects, can NOT be replaced with digital settings. In some of those cases, it may be possible to edit the photo with software to attain the same effect as using a filter. I’m of the school of thought that the end result will be strongest when most of the work is done in camera and there is less that has to be done in the digital darkroom. Start off on the right foot, and you will go further.

What do filters look like?
The three main styles of filters for photography are:
A round, glass filter that can be screwed on to the end of a lens.
A square filter made of glass or gelatin, used in conjunction with a filter holder, that attaches to the end of a lens.
A digital filter built into your camera and controlled through your camera settings.
All styles of filters are effective. There are pros and cons to each of them, but it really comes down to personal preference and usage.

Why would I use a filter?
Filters can be used to capture a more realistic reproduction of a scene. Conversely, they can be used to create a more artistic representation of your scene. Filters can make subtle differences in your image. Or, they can make dramatic changes. It all depends on your intent and filter choice. I know it sounds contradictory, but after experimenting with different filters, it’ll make more sense.

Black and White Filters
In black and white photography, filters are used to adjust shades of gray. The human eye can see about 200 different shades of gray. The eye perceives light differently than film or digital sensors. By using filters, photographers control shades of gray in order to reproduce a scene, photographically, the way it’s seen with the eye.

Black and white filters can be used on scenery as well as in portraiture. Let’s start by looking at the use of these Contrast Filters in black and white portrait photography.

These three images were all lit the same way, shot on the same film, with the same background and the same model. Yet, there are significant differences from one image to the next.

The first image is an unfiltered photograph, shot on black and white film. In the second photograph, I added a Red, No. 25 filter to my lens. This filter lightened the skin tones and lips, darkened the eyes and hair, as well as diminished blemishes. The third photograph was taken with a Green, No. 58 filter. In comparison to the unfiltered photo, the green filter increased contrast and darkened the model’s lips and hair.

Yellow filters (No 8. and No. 15) can also be used to lighten skin tones, in a slightly less dramatic fashion than No. 25. The No. 47 Blue filter can be used in B/W photography to darken skin tones, lips and hair.

These filters are also helpful in photographing sceneries. Use a yellow filter any time you’re shooting in snow, to increase contrast and get more detail. Use a red filter when shooting blue skies with clouds to prevent the blues from washing out.

Shot without a filter.

Check out the effect of a Red filter on the sky.

Filter Cheat Sheet

Use a Red filter to reduce blemishes.

Use a Green filter to darken lips, hair and increase contrast on the face.

Shooting Blue Sky: Start with a No.8 Yellow for a natural effect and then progress through to a Deep Red to darken your sky and make it more dramatic.

Landscapes: Reduce haze with a No. 15 Yellow or No. 25 Red.

Snow: Use a No. 15 Yellow or No. 25 Red to capture more detail.

This just barely touches on what can be done with these filters. The best thing to do is get out there and start shooting and experimenting. I’ll address other important filters, such as polarizers and split neutral density filters in another post.