Playing With Tone In Photoshop CS3. . .

First choose a photo or image that you would like to convert to tone.  Images with strong lines, less small detail, and the ability to push the maximum contrast levels without losing major focal points are the best choices.

A few years ago, my son, Andrew, decided to be Neo from the Matrix for Halloween.  This photo is perfect to convert to tone because there are definite areas of light and dark and there are no fine details that need to be preserved.  You may click on the thumbnails at right to view a larger version of each photo in this tutorial.

The first thing you will want to do, is give the photo a new name and save it as a new .psd image.  When that is done, go to Image>Mode>Grayscale, and when you are prompted, choose "flatten image".  This will dump all the color information and convert the photo to grayscale.  If you have saved the image under a new name, then you will still have your original color image stored under its original name.

At this point, you will want to click on the thumbnails for a better look at the tone in each of the next three steps.  Now you will go to Image>Mode>Bitmap, and when prompted, once again choose "flatten image".  An option box titled "Bitmap" will appear.  In the resolution portion of the box, you can adjust the resolution of the image you are using.  I have chosen to keep mine at 180.  In the method portion of the box, choose "Halftone Screen..." 

Next, choose Image>Adjustments>Curves (for greatest control), or Image>Adjustments>Brightness/Contrast (easier to use, but less control over the outcome), and enhance the contrast to the maximum you are comfortable with for the photo you have chosen.

A new option box will appear, titled "Halftone Screen.  This box will have three sections:  Frequency, Angle, and Shape.  The frequency section sets the size of the dots your photo will be converted to.  The lower the number, the larger the dots, and conversely, the higher the number, the smaller the dots. 

The default angle setting is usually 45 degrees.  You can leave it there, or if it is set to another number, change it to 45. 

In the shape section, choose the "round" option.   In the first photo with tone, I chose a frequency of 15.  In the second, I chose 10, and got lager dots.  In the last photo, I chose 20, and the dots are much smaller. 

Play around with it until you're satisfied with the outcome.  For the purposes of this photo, I like the frequency setting of 10 the best, because it gives the largest dots and makes the photo appear very comic-bookish.  Choose whatever you like and what will work best for the image you have chosen and the plans you have for it.

Like many things in life, it sounds much more complicated than it really is.   Once you get started, you'll find you have lots of images that can be converted to tone, and from there it's just a step away from turning your tone images into Photshop brushes.  But that's another tutorial...