There are many B/W conversion methods, two shown below. We will use one of the most effective techniques - Channel Mixer conversion. It is powerful, and it is fast. Make sure Monochrome is selected. This will give you a grayscale preview to work with. This mode uses up to 256 shades of gray. Every pixel of a grayscale image has a brightness value ranging from 0 (black) to 255 (white). Grayscale values can also be measured as percentages of black ink coverage (0% is equal to white, 100% to black). You can mix information from the color channels to create a custom grayscale channel by using the Channel Mixer command.
Important: Try to keep the total sum around 100 to avoid washed out areas in your picture.There is no real exact way to balance a picture, the most common black and white is based on the red colors that's why the channel mixer started out with 100% red.
Original image with two quick methods of RGB conversion to grayscale
Image/Adjustments/Desaturate
Quick and easy - but the image has very low contrast, and it appears "pale" and flat.
Image/Mode/Grayscale
Simple as that - but as you can see it loose some depth.
Color Images with strong colors that are going to be converted to grayscale (black & white) are best suited for this method. (See RGB/CMYK to grayscale for another good method).Here's the original image with a strong blue that will give you a 98% density when converted to grayscale which when printed will be a black solid!
You can see that the blue sky when converted to grayscale is to dark without any adjustment
However this is still an RGB image so by moving the Blue channel slider to the right we can reduce the density of the sky. However the tradeoff is we have lost some detail in the highlights (look at the rocks).
By reducing the value of the Red channel we can restore this (look at the rocks). This can now be converted into a grayscale that will print ok as opposed to one that would have a solid black sky! You can now use Levels or Curves to give it some final adjustments.
Important: Try to keep the total sum of the RGB channels to around 100 to avoid washed out areas in your picture.
 |
|
|
|
 |
|
||
 |
 |
 |
|
 |
|
||
 |
|
|
 |
 |
|