Monday, April 18, 2011

B&W conversion write-up

Here is the link to the write up in color hosted by Google Docs.


How to Convert your Color Image to Black and White using

Adobe Photoshop Elements 3 & 4 or Photoshop 6, 7, 8, & 9

Version 1.0 05/17/06

Seder Burns

General notes:

•First, create the best color image that you can from your image. See Figure 1

• Duplicate the color image numerous times. As you duplicate the file, take the time to

name the new files by the various techniques you are going to apply to each.

•Open up the histogram window and make note of how the tone changes between the

various conversion methods.

•Because the overall tone of your image changes once you convert it to black and white,

you will almost certainly need to perform additional tonal editing.

I have decided to group these various means by the programs that can perform them.

The following five methods work with all flavors of Photoshop

and Photoshop Elements that support Camera Raw without

the need for additional plug-ins.


See Figure 1

1. Conver to Grayscale Mode

Perphaps the most widely used method is to simply convert your image to Black and

White via the Grayscale Mode. Just go to the main menu and select Image > Mode >

Grayscale.

This will convert your image to black and white by desaturating each of the Red,

Green, and Blue channels and then averaging them together based on a predetermined

mixture which is designed to mimic traditional silver based black and white films.


2. Desature the image

From the main menu, simply go to Enhance > Adjust Color > Remove Color.

This simply removes the color without affecting the tonality of the image.


3. Gradient Map

This remaps the tones of your image to whatever color gradient you select. From the

Main menu select Layer > New Adjustment Layer > Gradient Map.

You will get a dialog box that allows you to rename it if you want. Otherwise, hit the

OK button.


Select the Black to White Gradient and then hit the OK button.

4. Double Hue/Saturation Adjustment Layer Method

This is definitely the most advanced method of black and white conversion that all

versions of Elements supports without the addition of any plugins.

First, pull up your Layer Palette. Then create a new Hue/Saturation adjustment layer

by clicking on the little circle that is half white and half black.


This will create a new Hue/Saturation Adjustment layer. Don’t make any adjustments

to this layer. Just hit the OK button. Then from the drop down menu, change the

blending mode from Normal to Color. Now create an additional Hue/Saturation

Adjustment layer. Drag the Saturation slider all the way to the left. Then hit the OK

button. Then open up the first Hue/Saturation Adjustment layer that you created. By

moving the Hue slider, you can change the overall color relationship of the image

before the second Hue/Saturation Adjustment layer removes the color. Thus, you can

affect the overall tonal relationship of the image by adjusting the Hue slider.

For even greater control, you can even work on different color ranges separately! This

is an extremely powerful and versatile means to convert an image to black and white.


5. If you shot the image as a RAW file (which you should always do if your camera

supports RAW capture), you can convert your image to Black and White within Camera

RAW. Simply slide the Saturation slider all the way to the left.

Notice the change in the histogram. Modify your Exposure, Highlight, Brightness, and

Contrast as desired.


The following Channel Mixer method work with all flavors of

Photoshop and Photoshop Elements 1, 2, & 3 (but not 4) that

have the Earthbound Light Effects for Photoshop Elements

plug-in. It is a free plug-in that greatly enhances the

functionality of Elements. It is available for as a free download

at http://www.earthboundlight.com/phototips/photoshop-

elements-curves.html.

Create a new Channel Mixer adjustment layer. The way you do this differs depending on

whether you are using Photoshop or Elements with the plug-in. In either case, you will

get the Channel Mixer dialog box.

Be sure to select the Monochrome option if it is not already selected. The default starting

point is 100% Red. The Channel Mixer works similar to the Grayscale Mode in that all

three of the channels are desaturated. However, unlike the Grayscale Mode method, you

can decide how much of each channel is utilized. With the default setting of 100% Red,

only information from the Red Channel is utilized.


Red Channel at 100%

Green Channel at 100%

Blue Channel at 100%


This generally leads to a very high contrast image in which flesh tones will appear very

light and blue skys will appear very dark. You should also see how the image will look

with Green at 100% and then Blue at 100%. The key to using this method is to keep the

totals adding up to 100% (or very close to it). You may find that you like certain

attributes of the image in both the Red and the Green Channels. So you might try 50%

Red and 50% Green. The whole idea here is that you can mix the channels until you get

the desired result. For a radical effect, try introducing negative values. The image below

is set at -100% Red and 200% Green. Notice that the values still total 100%.


The following LAB method work with all flavors of Photoshop.

So far, I haven’t found a means to achieve the same thing in

Elements.

This method consists of converting the image from RGB Mode to LAB Mode. LAB

Mode is another color model. It separates the tonal information from the color

information. This method simply preserves the tonal information while discarding the

color information.

From the Main Menu, select Image > Mode > Lab Color.

Then open up your Channel palette. Click on the Lightness Channel. It will become the

only active Channel. Then, from the main menu select Image > Mode > Grayscale. You

will then have a black and white image in Grayscale Mode.


The disadvantage of the LAB color method is that you can’t control the relationship of

tones based on color. The advantage is that the image features exceptionally clean

gradations of tone. It also creates a black and white conversion that is unique from all the

other methods.

Evaluating your Conversion?


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