Colours into tones in black-and-white

In this exercise, colours are completely desaturated in order to see how changing the relative brightness of yellow, red and green can affect the tonality of a black and white. It is designed to demonstrate that colour relationships affect black and white images as well as colour images.

I used a similar set up as the example in the notes - peppers are an obvious choice for demonstrating the required effect, a piece of broccoli providing some green.

f22; 1/60 ISO 400

This image was then imported in the Photoshop Raw Convertor and the basic convert to grayscale applied. The resultant neutral image is:

A succession of filters were then applied using the colour sliders in the Raw Convertor. I kept a record of the exact amount of adjustment as follows:

Filter	Red slider	Yellow slider	Green slider	Blue slider
Natural	0	0	0	0
Red	+70	-40	-100	-100
Yellow	-100	+100	-100	-100
Green	-100	-40	+100	-100
Blue	-100	-40	-100	+100

The resultant images are set out in the order above:

red filter

yellow filter

green filter

blue filter

There is evidently a greater degree of contrast when filters are applied as by definition one colour is exaggerated at the expenses of the others. This is especially noticeable with the yellow filter; not only is the yellow pepper almost burnt out by the filter but the red one becomes much darker. The blue filter affects the background.

Two main learning outcomes from this exercise:

1) colour filters can be used to good effect in black and white images;

2)  need to look at effect of changing filter on all the colours, not just the most obvious one.

Primary and secondary colours

The object of this exercise is to find scenes or parts of scenes dominated by one of the primary or secondary colours and vary the exposure slightly on each.

I managed to take most of the images while away for a few days in Cornwall - as mentioned in learning log, am getting accustomed to looking ahead; this generally means at least half the images I need have been taken by the time I get to the exercise. In this case only needed to add the orange.

The exercise notes suggested taking 3 exposures - one as camera meter suggests, one half a stop brighter and one half a stop darker. I found this was not enough on the Canon 450D so went for a full stop each way.

I deliberately chose to take a range of artificial and natural subjects.

Each of the set of images below is ordered overexposed, median exposure, underexposed.

The first primary colour is blue. This image was taken of the sky above Wembley on FA Cup Final day.

Blue is the darkest of the three primaries; this is apparent in the above images - even the brightest is not very bright (compared, say, to yellow below). Sky seemed a very obvious candidate for blue with added benefit in this case of some interest with the aircraft lines and clouds. The only slight downside is that the colour is not solid with some gradation in the picture.

Which is closest to the blue in the circle? Well actually none of them as my eye finds the blue in the circle to be impure, more of a dark violet. Probably the darkest is closest.

Yellow was an artificial colour - a pile of fishermen's crates at Polperro.

Possibly because these were a fairly dark yellow, the closest of the above images to the circle yellow is the brightest. This does emphasise that in practice we are presented with colours that may be anywhere on a wide range of brightness.


I took the entrance door to Looe fire station for red.

I noticed with the post box in the first exercise that red changes hue with brightness and this is evident here, with the brightest image being nearly orange, and the darkest almost a burgundy. The median exposure is clearly the nearest to circle red.

Turning to the secondary colours, I chose an avenue of trees shot in Brasov for green

The closest green to the circle green is again the median.

For orange, I chose a close up of a chrysanthemum.

The additional notes refer to the fact that photographers mainly have to deal with found colours, i.e. those that occur in the real world - artists have to concern themselves less with this phenomenon as they can choose pure colours on their palette. This is a good example of found colours - the orange is a pleasant colour but has areas on the tips of the petals of a different hue, where the orange becomes more of a broken colour.

To my eye, the brightest image is by far the most preferable as it gives off the radiance associated with the colour, but the orange in the darkest is actually the closest to the circle colour.

As other blogs have mentioned, violet is the most difficult of the six colours to find. I saw an opportunity with a child's coat hung on a buggy.

The brightest violet looks more overexposed than any of the other brightest images - perhaps not surprising as violet is the darkest of the six colours on Goethe's scale. The overexposure seems quickly to reduce the saturation.

Both the median and darkest images are reasonably close to the violet in the circle, probably the darkest is slightly closer.

An interesting and quite challenging exercise. It cements the concept that the degree of hue is affected by brightness and helps to emphasise the need generally to judge on a very specific basis - there is no general them that can be adduced from this exercise. I generally shoot half a point underexposed when outside in bright light ans experience has shown this mitigates against burnt out areas; this exercise supports that practice for the darker colours (blue and violet) but not the brightest (yellow and orange, for both of which the brightest exposed image looked best).

Colour relationships

This exercise is designed to explore the relationships between colours.

The first part is prescriptive: take three shots demonstrating the opposing colours with the object colours in the proportions set out below:

red:green, 1:1,
blue:orange, 1:2;
yellow:violet, 1:3

Not an easy task.

For red:green, I was tempted to reuse an image taken for an exercise in Part two Elements of Design of apples in an inverted triangle:

I am interested in the idea that one can use an image to demonstrate more than one concept. Here we have an inverted triangle, but also it demonstrates a sound red:green colour relationship, with a good approximation to 1:1 proportions. To me, SEEING the opportunity of reusing material is as important as he taking of new images. It promotes one's imagination.

Nevertheless, I though as well that an original image should be used, so took the following image at the FA Cup Final between Manchester City and Stoke City:

f5; 1/250; ISO 64

This was taken with a point and shoot camera. On a close up of the crowd, the image is a little blurred but at this scale hardly seems to matter.

The proportions of red (the Stoke fans) and the green of the pitch are very much in line with the 1:1. As a colour relationship, it works well. There is a sense of harmony, assisted by the same level of relative brightness.

f13; 1/20; ISO 200

The orange:blue is demonstrated by an image of boat covers taken in Looe harbour. It was an opportunistic shot, although I had the camera that day with one eye on shots for this exercise.

I have to admit that I took the shot without checking settings. I generally use aperture priority as a general setting as advice is that most lenses optimise at f9-13, so try to use these where possible. Problem was that the light was very poor and consequently ended up with a shutter speed that is really too low for hand hold. The much maligned (by professionals) P setting would have been fine here, or else use shutter priority. Is it a lesson learnt? I doubt it as I do tend to forget settings occasionally - getting better but still happens.

Again, on this scale and for this purpose the error scarcely matters. I cropped the image to fit the blue:orange 1:2  proportions, leaving part of the aerial in for some interest. For this exercise, the image works: the colours do harmonise, and what comes out strikingly from this is the brightness of the orange - even at 2:1 it is the more dominant colour in the image, perhaps not helped by the somewhat dirty blue.

f22; 1/4, ISO 800

I took a still life for yellow and violet, arranging a yellow pepper on a violet background and setting up the camera on a tripod with Speedlite flash on the right, thus balancing the natural light from the left. Shutter speed is arguably low to use with a flash but I was happy with using f22 to get good depth of field and the Speedlite seems to adjust well to shutter speed. The big advantage of a still life is being able to get the proportions as required - 1:3 yellow:violet in this case.

I guess this works from the point of view of the exercise. Hardly a gallery shot but I am convinced of the greater harmony produced by having the colours in these proportions.


The second part of this exercise is much more of a free reign - produce three or four images featuring colour combinations that appeal to me.

f11; 1/125; ISO 640

I used the opportunity presented by the graduation of twin sons on two separate days in July to take shots of colour combinations. Graduation gowns are a perfect subject for this and I particularly liked this shot of the contrasting blue and red. The image is sharp yet the silky textures come out well and there is depth created by the lighter band of the hood in this image. These all help to add interest to the colour contrast.

f11; 1/500; ISO 200

I took this shot of the sign for a Chinese takeaway in Leicester as I think it demonstrates how contrasting colours (in this case red and yellow) do not work well together. There is a distinct lack of harmony, perhaps not helped by a lack of a dominant colour in the relationship.

f6.7; 1/180, ISO 200

Lavender is an obvious choice for a violet subject, here taken with some evening light enhancing the green stalks. Not original, but a pleasing image with the variation of light adding interest.

f16; 1/60, ISO 200

The last image is an arrangement of four of the primary colours. The shot is of flower pots above a Leicester pub. Credit here to the originator of the arrangement; perhaps he or she has seen that shrubs can be enhanced by placing them in a colourful arrangement of pots. I cropped a lot of the image, concentrating on the line of pots. For me, the image demonstrated the power of colour, primary colours in particular. There is little interest without the colour.

This was not an easy exercise - I found it challenging to take images meeting the brief of the first part in particular. It has helped to cement my knowledge of colour relationships and to think about their proportions when composing or cropping images. There was also the basic issue of checking settings discussed above that needs constant attention.

Colour

Generally I have avoided making notes on the course notes as I think one can take as a given that they are read as an integral part of and precursor to the exercises; the exercises themselves are evidence of reading the course notes.

I make an exception here however as there is on p85 of the notes a reference to additional material on Colour that is advisably read before progressing to the exercises. I have already completed the first exercise but it is a relatively simple exercise. Before completing further exercises it seemed sensible to read the additional notes, and to make some notes on these in the learning log.

Colour creates deeper responses than the simple visual response induced by the graphic elements; works in 3 ways:  Visual - the objective immediately obvious level;
Expressive - emotional level;
Cultural - certain combinations associated with things we have grown up with;

Qualities of colour
Hue - prime quality that can be influenced by light or filters;
Brilliance
Saturation - measure of pureness of colour - desaturated when mixed with other colours.

Primary colours
Yellow - brightest and lightest of colours, vigorous and sharp;
Blue - darkest primary. Cool, suggest reflectiveness.
Red - powerful colour, relatively dense and solid.

Secondary colours
Orange - brilliant and powerful. When lighter, suggests warmth;
Violet - elusive. Pure violet is darkest colour, lighter is lavender. Creates impression of mystery and immensity.
Green - most visible colour

Basic colour combinations: red/green, orange/blue, yellow/violet.
Generally accepted light values determined by Goethe are Yellow 9, Orange 8, Red and Green 6, Blue 4 and Violet 3

Red/green harmony - same luminosity produces vibration, edge between colours appears unstable.
Blue/orange - as orange is twice the luminosity of blue so blue should be twice the area.
Yellow/violet - brightest and darkest requires 1:3 for balance

Multi colour combinations - groups of pure colours make easy, attention grabbing shots.

Broken colours
Unlike Art, photography has to work with real world colours where purity is less common although this helps eye to "be delicate in its discrimination".

Black and white
Black is maximum density - Dmax
White is absence of tone - careful to get exposure correct.

Distance
Cool colours recede, warm colours advance. Cool suggest wetness, orange/red dryness

Control the Strength of Colour

This exercise is part of the general project of what makes colour. Of the three qualities that make colour - hue,saturation and brightness - it is the last that is the subject of this exercise.

We needed to find a colour that would fill the frame - I chose a postbox - and then take five images, 2 successively underexposed, an average exposed image, and two overexposed. From darkest to lightest, the images appear as follows:

f6.7 1/180 EV-2

f5.6 1/125 EV-1

f4.5 1/90 EV0

f4.0 1/60 EV+1

f4.0 1/30 EV+2

Rather than use aperture changes as suggested in the text, I adjusted the Exposure Value and P mode on the camera, letting it set the relative aperture and shutter speed settings. Depth of field is not an issue here.

My camera is set to half point increments so my images are taken at twice the range suggested in the notes; looking at the results, this seems a justified modification.

Looking at the results, we can see that the colour changes from a deep burgundy at the lowest exposure, through red (genuinely postbox red) at the average, almost to orange on the brightest image with intermediate stages between.

From this exercise, I learnt to respect exposure (and brightness) not just as factors in their own right, but also in a way that affects the colours in an image - the colours do not simply become brighter or darker, they actually change in pigmentation appearance. An important lesson in digital processing.