A quick look at using coloured filters in black & white photography
Rishi – one of our students – just nudged me to write a long-overdue piece here about the use of coloured filters in black and white photography. The effects are quite the same using them with digital as film, as different emulsions of film [and the nature of film itself, being an organic material] meant different effects. However, applying them to digital cameras can produce some good effects which are usually just not as pronounced as when done with film.
So, let’s take a basic look at the whole notion of using coloured filters on black and white photos. Sounds a bit daft doesn’t it? We’ve got a black and white film in the camera or our DSLR set to shoot in mono and we’re adding colour. Hmm. Well, it comes down to this:
Normal black and white camera films [and DSLRs set to shoot in mono] are sensitive to all wavelengths of visible light, but do not mimic the response of the human eye very closely; colour filters allow us to modify the way the film will respond to the different colours of the scene.
The basic rule of thumb is that same colour filter as object in front of lens? Object colour goes lighter. Opposite colour [green to red, red to blue, etc] darkens the colour in front of the lens. So a blue sky photographed with a red filter makes the sky go dark. Trees and grass photographed with a green filter makes the greens go lighter.
Not just useful if you are planning to shoot in black and white, but very useful info if you do black and white conversions of your shots in post-processing and want to know how to mix up the colour channels to best effect.
The images below are all shot on my Nikon D700 with the standard ‘monochrome’ picture control and colour filters applied digitally by manipulating the variables in the ‘Manage Picture Control’ menu. The choices of coloured filter are, in the D700; yellow, orange, red and green.
The shot was taken using a 50mm lens set to f/5.6 and 1/60th second. Flash was used at 1/64th power on an SB800, diffused through a Lumiquest Softbox 3.
Here is a shot with all of these filter pictures placed side-by-side for easier comparison. Each is discussed below with its own picture. Click this picture to get a nice, large version.
Thanks, Ami, for letting me borrow her coloured pens and to Joe for agreeing to pull funny faces for the headline photo….
Colour reference photo:
The Yellow Filter:
This is what I’d bring out the bag when I didn’t want quite the marked effect on skies as with a red or, if there were red objects in my landscape I didn’t want to lighten so much. A yellow filter has always been the “classic” first choice filter for the user of black and white film. It gives an excellent balance between photographic effect and ease of use.
Many photographers use a yellow filter to “bring out the clouds”. It does this by darkening the blue of the sky, hence there is much greater visual separation between the darkened sky and the white clouds on the final print. A yellow filter will also give improved penetration of haze and fog.
Although a yellow filter darkens blue, it reproduces green, yellow, orange and red in lighter shades. This gives more differentiation between different colours of foliage and flesh tones have a more natural look.
A typical yellow filter will have a filter factor of 2; the manufacturer will supply the exact factor with the filter. Most cameras with TTL metering will correct automatically for the filter factor but check the camera instruction book.
The Orange Filter:
An orange filter gives effects which are stronger than those given by a yellow filter but not as bold and dramatic as those given by a red filter, hence it is ideal choice to span the effects given by both these filters.
Blue skies will be recorded in very dark tones on the print, giving bold contrast between the sky and clouds. An orange filter will also penetrate haze and fog. Most flowers will be recorded with a significant difference in tone from the surrounding foliage giving impact and effect.
An orange filter is excellent choice when bold and dramatic effects are required.
A typical orange filter has a filter factor of 4; the manufacturer will supply the exact factor with the filter. Most cameras with TTL metering will not be able to automatically correct for the filter factor. Due to the dramatic effects given by an orange filter it is recommended that an additional shot is taken giving +1 stop extra exposure.
The Red Filter:
A red filter is typically used to give bold and dramatic effects to many photographs, gone are the more subtle changes giving by both yellow and orange filters. Blue skies are now recorded as black on the print, resulting in an impending thunderstorm effect. Pictures of mixed material buildings gain drama and clarity. A red filter will also give marked penetration of haze and fog.
My Monochrome-02 Nikon Picture Control uses the red filter in conjunction with extra brightness and contrast to really whiten skin. I might also use, on film, a red and a polarizer together, to control reflections, darken skies and water more and add contrast. This also works on digi with an optical polarizer and a digitally applied red filter.
When taking pictures of flowers without a filter there is often little difference in tone between the flowers and the foliage in the print. A red filter will, in almost every case, give a significant difference in tone, so making the photograph more interesting and dramatic.
A typical red filter has a filter factor of 4 to 5; the manufacturer will supply the exact factor with the filter. Most cameras with TTL metering will not be able to automatically correct for the filter factor.
The Green Filter:
A green filter is used almost exclusively in black and white photography for photographing foliage.
It will lighten green foliage, which is particularly important with dark green leaves which can record very dark without a filter giving a more natural, lighter feel to the photograph.
A typical green filter has a filter factor of 2; the manufacturer will supply the exact factor with the filter. Most cameras with TTL metering will be able to correct automatically for the filter factor.
The Blue Filter
A blue filter is not often associated with use in black and white photography.
However, it can really add “mood” to a photograph by increasing the effect of haze or fog. It also lightens blues and darkens yellow, orange and red which can help give separation to a photograph containing mixed colours. Blue filter makes skin look awful.
The Nikon D700 does not have a facility to add a blue filter.
I will be shooting similar shots with colour filters applied optically, in front of the lens and will post those when they are finished.
A Couple of useful links: