convert colour image to black and white

[mplbm]

Is it possible in Photoshop to take a colour image and convert it to a black and white image?


Thanks,

Mike

 

[kim00]

mplbm - image | mode | grayscale will do it... kim

 

[mplbm]

Thanks Kim!

 

[blueark]

When professional photographers are shooting in black & white, they'll often employ the use of color filters to create a more striking image. Variations of this technique are often used in Photoshop before the image is converted to grayscale. For example:

1: Create a Hue/Saturation layer above the color image, and reduce the saturation to -100 to get rid of the color. Then, in between this layer and the color image, create another adjustment layer, such as Curves or another Hue/Saturation -- basically anything that can adjust individual color channels until you get the effect you want.

2: Instead of creating two adjustment layers, create one Channel Mixer layer, check Monochrome, then adjust the different color sliders. This is my personal preference, but it takes a little practice to get it right.

Once the image is as you want it, you may want to convert it to grayscale if you're working in single color printing. These techniques are sometimes overkill, but for a professional result, you should try and control the conversion process as much as possible.

 

[kiddpete]

I don't convert it to grayscale unless there is no other choice. The channel mixer is a much better choice since it does not discard the detail within each color channel.

 

[jimoblak]

Depending on your version of Photoshop, you might get a better conversion than RGB - grayscale by first converting RGB - LAB, then deleting the A&B channels, and then converting to the grayscale mode.

 

[elf21]

Not my post - but was wondering how to use the channel mixer. Is there a certain set of numbers to use or is it just trial and error??

 

[blueark]

The numbers you use depend entirely on the image, and the effect you are trying to achieve. For example, in an RGB image, reducing the Red value will make reds appear darker, and increasing the other values will give other colors a lift. Alternatively, decreasing the Blue value can help to create a more dramatic sky, for example.

In CMYK mode, the sliders act in reverse (increasing values makes them darker), but the principles are still the same. Try it out for a while and you'll soon get the hang of it.