The process for this exercise was to take one colour photograph of pure, high contrast colours and applying differing coloured filters (default, red, yellow, green blue), produce several black and white images from the original photograph. Then I was to note the physical differences in these photographs according to the colour of filter applied. I also included a piece of medium grey card to act as calibration point (i.e. it will be unaffected by the applied filters. If it were to change colour/lightness then I may have applied an impure filter or introduced some other incorrect adjustment). Below is the original image followed by the black and white images with different filters applied. The filters I have used are the standard black and white colour filters in Aperture. The application of each colour filter entails the slider of the corresponding colour being pushed to 100% (or equivalent). This will give me a clear idea of the effect of each. I shall comment on each individually.
The colour image includes the three primary colours: red, yellow and blue on a strong green background. This will give the most easily definable visual results once the filters are applied.
This default filter gives each colour an even presence in the frame. The image shows almost a low-contrast graduated greyscale from yellow to blue. The sliders are all positioned at ‘0’ or neutral.
This image is extremely high contrast. The blue has practically disappeared into the green background so dark are they both. The yellow is almost white in colour (even compared to the grey card, not just the background). The red slider is pushed to 100%.
A more even distribution of greyscale in this image and much easier to see the individual bricks that make up the letters of the colours. The yellow bricks appear to have darkened slightly in comparison to the previous image. The yellow slider is pushed to 100%.
As I would expect, the green background has lightened significantly in this image. The red is very dark. There is quite a wide range of greyscale here. Again yellow stays quite neutral. The green slider is pushed to 100%.
Blue has lightened significantly. Yellow, for the first time in this series, is very dark (as dark as the red). The blue slider is pushed to 100%.
An interesting exercise as I don’t tend to pay attention to the type of filters when I convert to black and white. I generally experiment to see what looks ‘right’. Of course these images all show the extreme version of applying any particular filter but it is extremely useful to take note as when I am shooting for black and white (I don’t have a black and white monitor facility on my camera), what each colour is likely to look like in the final image. Given this information I can consciously shoot differently for black and white when given the opportunity. I have always looked at the light and form contrast (black and white) when shooting rather than look at the colours which could also dramatically affect the outcome.