The image I settled on was a portrait of my son taken during the portrait exercise in Project 1.
This is the original colour version.
|Default Black and White|
Alteration using one of the default settings within CS4, I chose to use a Black and White adjustment layer. The background appears to be darker, in this particular instance, when converted to black and white. Skin tone also appears a little darker and the image to me, looks slightly flat. The subject no longer appears so "separate" from the background.
|Default Channel Settings|
These were the Channel settings before being adjusted.
|Side by Side to Compare|
Placing the two images side by side for comparison shows how very subtle alterations to the Channels can improve default conversions. The changes made to Red and Yellow have made for a more natural looking complexion and helped to make the main subject stand out from the darker background. This exercise has also shown me how some Channels can effect more of an image than others. Converting to Black and White and making use of the adjustments available in Channels can make a seemingly uninteresting image more appealing/atmospheric and even allow you to rescue other photographs where you would be unable to correct the colours/tonal range without making the final result look fake.