2.1
File>Open – Navigate to the folder holding the
image to be processed and open it.
2.2
Check that the default colours in the toolbox are set
for black and white as the foreground and background respectively.
2.3
Copy the ‘background’ layer and rename it
‘black and white’.
2.4
Image>Adjustments>Channel Mixer – Tick the
monochrome box and you will observe that the Red Source
Channel is showing a value of 100%, Green Source Channel
0%, Blue Source Channel 0% and the Constant is 0.
2.5
Click on the ‘black and white’ layer
2.6
With the Red Source Channel showing a value of 100%, move
the Green Source Channel slider to –50% and the
Blue Source Channel slider to +50%. Check the effect.
Keeping the Red Source Channel slider maintained at 100%
move the Green Source Channel to –100% and the Blue
Source Channel slider to +100%. Check the effect. Continue
with these Green & Blue Source Channel incremental
changes until –200% and +200% respectively is achieved,
checking the effects that it produces. Repeat the whole
process of incremental changes, swapping over the Green
and Blue Source Channels and holding the Red Source Channel
at 100%. Once again check the effects.
2.7
With the Green Source Channel set to 100%, repeat the
above process with the Red and Blue Source Channels, noting
the effects that they produce.
2.8
With the Blue Source Channel en Source Channel
set to 100%, repeat the above process with the Red and
Blue Source Channels, noting the effects that they produce.
2.9
Now that most permutations of Red, Green and Blue Source
Channels have been tried, identify the effect which has
produced the most desirable tonal result.
2.10
File>Save As - Navigate to the deired folder and save
the image.
