Camera Lens Filters

• can enhance colors, add special effects and reduce reflections

• can protect lenses for capturing scenery in extremely difficult lighting conditions

• are often necessary to modify the light before it enters the lens

• at the same time, lens filters can actually hurt photographs if they are not properly used

Lens Filters

Notes on Choosing a Filter for a Camera Lens

Lens filters generally come in two varieties:

1. Front filters – more flexible = can be used on virtually any lens diameter; may also be more inefficient to use since they may need to be held in front of the lens. On the other hand, filter holder kits are available that can improve this process.

Front Filter Holder Ring

Notes on Choosing a Filter for a Camera Lens

Lens filters generally come in two varieties:

2. Screw-on filters – can provide an air-tight seal when needed for protection, and cannot accidentally move relative to the lens during composure. Disadvantage: a given screw-on filter will only work with a specific lens size.

Screw-on Filter

Notes on Choosing a Filter Size for a Camera Lens

Screw-on filter- expressed in terms of its diameter, which

corresponds to the diameter usually listed on the top or front of your camera lens

- listed in millimeters and usually ranges from about 46 to 82 mm for digital SLR cameras

identifying the size

Notes on Choosing a Filter Height for a Camera Lens

• the height of the filter edges may also be important• ultra-thin and other special filters are designed

so that they can be used on wide angle lenses without vignetting (the reduction of an image's brightness or saturation at the edges compared to the image center)• but may also be much more expensive

vignetting

vignetting

vignetting

Types

1. Circular screw-on filters• most common• mounts directly on the lens filter thread• e.g. UV/Clear/Haze filters, circular polarizers,

neutral density and color filters

circular screw-on filters

Types

2. Square filters• a popular choice for landscape and other

photography• a filter holder directly attaches to the lens filter

thread and can hold one or more filters• the most popular sizes are 3×3 and 4×4• can be stacked together in certain situations,

which can negatively impact image quality and add reflections.

square filters

Types

3. Rectangular filters• another popular choice, primarily among

landscape photographers• mounted just like square filters via a filter holder

system• unlike square filters, they have more room to

move up and down• the most popular size is 4×6, although larger and

smaller filter sizes are also available

rectangular filters

Types

4. Drop-in filters• these filters are used inside long telephoto

lenses, due to the large size of the front lens element

• only clear and polarizing filters are used for drop-in filters

drop-in filters

Filter Factor

• filters change the dynamics of the light entering the lens and usually require you to alter your exposure to compensate for this fact which is called Filter Factor• each filter has a specific filter factor

Filter Factor

1. UV filter• transparent filters that block ultra-violet light

to reduce the haziness that is noticeably apparent in some daylight photography

• doesn’t affect the majority of visible light, so it’s a perfect form of lens protection and it will not alter your exposure

Filter Factor

2. Polarizing filter• can be used to darken overly light skies as it

increases the contrast between clouds and the sky• like the UV filter, the Polarizer reduces

atmospheric haze, but also reduces reflected sunlight

• most typical function: to remove reflections from water and glass

• two types: linear and circular

Filter Factor

3. Color Balancing filter• use this to affect a change in your light sources

and to compensate for the various differences in the photographed color of light

Filter Factor

3. Color Balancing filter• 85B (warm-up/orange filter) enables you to

shoot in the daylight when the white balance/color temperature is set for tungsten. Without the 85B filter, your image will have a blue color cast to it

Filter Factor

3. Color Balancing filter• 80A (cool-down/blue filter) enables you to

shoot under tungsten light when the color temperature/white balance is set for daylight. Without the 80A, your image will be abnormally warm/reddish orange

Filter Factor

4. Neutral Density filter• reduces the amount of light entering the lens• is helpful when the contrast between the

highlights and shadows is too great to get a quality exposure

• can enable greater motion blurring and image detail by allowing a large aperture and/or a slow shutter speed to be used

Filter Factor

5. Soft Focus filter• reduces the sharpness of an image, but only to an

extent that is barely noticeable• useful in shooting close up shots of people’s faces• with the help of a little diffusion; imperfect skin

conditions are replaced by silky smooth skin• you can use soft focus filters while photographing

landscapes or monuments as well

Filter Factor

6. Filters for B&W Photography• there are specific filters for B&W photography

that lighten similar colors and darken opposite colors, thereby enhancing the monochromatic look

Filter Factor

5. Filters for B&W PhotographyRed filters

• are a favorite among landscape photographers and are often used to add drama

• in nature photography, this will increase the contrast between red flowers and green foliage

• will deepen a blue sky and make white clouds pop out• can also decrease the effects of haze and fog• in some cases, depending on its strength, a red filter

could even turn the sky black

red filter

Filter Factor

5. Filters for B&W PhotographyOrange filters

• increase contrast between tones in textures such as tile or bricks, making it a good choice for general use and urban or abstract photography

• it also helps to decrease haze and fog, but it’s effects on the sky and clouds are subtler than the red filter

orange filter

Filter Factor

5. Filters for B&W PhotographyYellow filters

• subtler than orange filters, making it a ‘classic’ choice for beginners just starting to explore using filters with black and white photography

• helps to darken the clouds slightly, and it also separates light green foliage from the darker shades of green

yellow filter

Filter Factor

5. Filters for B&W PhotographyGreen filters

• lighten dark green foliage and boost light green foliage

• have a more specific use and are not as commonly used as the other filters, but these are extremely useful for nature photographers

• may lighten the sky, so landscape photographers should take note of this when using it

green filter

Filter Factor

5. Filters for B&W PhotographyBlue filters

• not as commonly used in black and white photography because they lighten the sky and darken highlights or colors that are seen as light

• can draw attention to haze and fog, which can enhance the mood of the photo if needed

blue filter

Conclusion

Photographic filters• are used to achieve image enhancement effects that can

change the tone and mood of your photographs• inject slight, but noticeable alterations to your image• unlike editing softwares, you can immediately see the

difference to your image in the viewfinder when you use a filter

• the effects of filters are more pronounced when working in B&W, as the monochromatic tonal scale reacts much differently, and also with greater dramatic affect

References:• Lens Filters | Camera Lens Filters Explained. Retrieved from

http://www.exposureguide.com/lens-filters.htm• Choosing a Camera Lens Filter. Retrieved from

http://www.cambridgeincolour.com/tutorials/camera-lens-filters.htm• Lens Filters Explained. (2011, September 8). Retrieved from

https://photographylife.com/lens-filters-explained