Greyscale vs. Desaturating Photo

[Woodman7]

This may be a really stupid question, but I am going to ask it anyway. I have been doing alot of work with black and white photos. When I first read how to make a photo black and white in photoshop, I read that you use the desaturate feature. I have since found how to make the photo greyscale. I did a side by side comparision and I couldnt see a difference in the black and white. Is there a difference?

[evilenglishman]

--

[DAMphyne]

There is a difference with the Mode on your photo. If you change to grey, you loose the chance to adjust the channels,RGB, independantly. Sometimes having that option will help to tweak the photo. Also, some printers work better with RGB than grey.

[lziering]

The best way to turn a color image into b&W in Photoshop is to use a Channel Mixer layer.

First, go to the channels palette and click on each channel one at a time (red, green, blue) and look at how each channel looks different. Channel Mixer will allow you to choose the mix of the three channels that creates the best B&W representation of your image. For instance, you might have a nice landscape shot with big puffy clouds. This will usually look best in the red channel. You might have a nice shot of a kid with freckles and these will be most visible in the blue or green channel. If you have a shot of a woman you will see that her skin looks best in the red channel.

Once you've finished looking at the three channels go to the bottom of the Layers Palette click the buttom to creat a new Channel Mixer layer. Click "monochrome" at the bottom of the dialogue box and move the sliders to produce the best b&w for your image. Try to have all three channel add to 100%. If you want to reduce the file size you can convert to greyscale after you complete the Channel Mixer step but I would not because you might want to change the mix later.

Experiment with the channel mixer. Try using a negative value for one of the channels or try using just the red channel (looks a lot like infrared).

Channel Mixer is an amazing tool. It can also be used to improve the look of color images. Similar technique to the one above but you change the apply mode for the layer from from "Normal" to "Luminosity". For instance on a close-up of a woman you can set the red channel to 100% and the others to 0%. Click "Monochrome" and Okay and then set the layer apply mode to Luminosity. Play with the Opacity Slider until you get a nice soft glow on her skin which will hide her pores and wrinkles.

Good luck.

[martcol]

Have a look at this very interesting technique for B&W conversion.

http://www.russellbrown.com/body.html

Look for the ColortoB&W.mov

Martin

[Woodman7]

Thanks alot guys for the information. I am glad to see that it wasn't such a stupid question after all. Hopefully it has helped someone else in the process of asking it. Iziering I will try your suggestion and thanks for taking the time to post

[The Photo Tuell]

I like that Russell Brown method. Very versatile but easy to figure out with his explanations. Toughest part is deciding what changes look the best.

Can you tell which is greyscale and which is Russell Brown method? (originals here (http://www.pbase.com/the_photo_tuell/tuell_picnic), at the bottom)

http://www.pbase.com/image/20479942/medium.jpghttp://www.pbase.com/image/20975899/medium.jpg

[evilenglishman]

--

[perfectpixel]

Can you tell which is greyscale and which is Russell Brown method?

greyscale on the left, eh?

[Woodman7]

I would have to say I think the greyscale is on the left as well?

[Motorsports Photo]

lziering wrote:
The best way to turn a color image into b&W in Photoshop is to use a Channel Mixer layer.


Hey, thanks for that cool tip. I was playing a round with the channels one day and forgot to turn them all back on and printed out a nice B&W print. Now I know a much better way to do it when I need that occasional B&W pic.

-Pete