| First technique - Desaturate + Levels |
| This is the basic technique to convert color photos to b&w. It offers little control over the image compared to other methods but it's the easiest and the fastest. |
| Open your image in Photoshop |  |
| Click on the menu Image > Adjustments > Desaturate (or simply press Shift+Control+U) |  |
| As you see your image turned to black & white. What you may notice too is that the photo is a bit flat. Let's take care of that. |  |
| Click on the menu Image > Adjustments > Levels (or simply press Control+L) |  |
| A similar dialog to the one the left will appear showing an histogram. As you can see there are 3 triangles below your histogram: the first one from the left - black point slider; the middle one - gray point slider; and the last one on the right - white point slider. First, drag the black point slider until you're happy with the black point you achieved in your image. Again, do the same to the white point slider. Finally, if you want to add extra contrast control between these two points just drag the gray point slider (middle one) to one side or another. Remember to tick 'Preview' to see what's happening with your image when you drag the sliders. Click 'OK' when you're satisfied with the overall result. You can see my final point in the second image here. Note: Levels is used also in color photography editing and delivers fast results | 
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| And here's the final image. |  |
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| Second technique - Channel Mixer |
| This technique allows you extended control over the results and throughout the process. |
| Open your image in Photoshop. | |
| Bring the Channels up either clicking in Window > Channels or simply clicking on 'Channels' tab in the small docked window (if it's active). Here you can see each channel: RGB (mixed color channel), Red, Green, Blue. |  |
| If you click each channel or press Control+1, Control+2, Control+3 you will see Red, Green, Blue respectively. What you see here is each channel separately. Pick one that you think is best to what you aim for and click again on the RGB channel in the same tab or press Control+~. | 
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| Next, click on Image > Adjustments > Channel Mixer |  |
| The following dialog will appear. |  |
| Click the 'Monochrome' option and notice you're not mixing the RGB output channels anymore but the Gray channel instead. Remember that channel that you picked before? Well, it's time to put that to proof. Increase that same channel too 100% while setting the other two to 0%. Try this step with the other two channels until you are satisfied with the image. Just make sure the total sum of the mix is about 100%. Now, try to mix them to get the image tonalities of black and white as you prefer. Click 'OK' when you're completely satisfied. |  |
| Here's the final image of this tutorial. The great thing about this technique is that you have full percentage of each channel by itself and mixed with the other two. |  |
