Photoshop’s Channel Mixer command produces grayscale images by letting you choose the percentage of contribution from each color channel. The Channel Mixer modifies output, in this case grayscale, color channel using a mix of the existing image’s color channels When using the Channel Mixer, you add or subtracting data from a source channel to the output channel.
Step 1: The original image was captured in RAW mode using a Panasonic Lumix G5 that was converted to IR capture by LifePixel. Exposure was 1/640 sec at f/9 and ISO 400. The image was then opened in Adobe Photoshop.
Step 2: The next step is opening Channel Mixer (Image > Adjustments > Channel Mixer.) Be sure to check the Monochrome option to set Gray as the output channel. This creates a color image that only contains gray values. Move the sliders to control the amount of detail and contrast in the image you plan to convert to grayscale but first view how changes in each source channel affects the final monochrome image which is “live” as you work on it. Tip: When adjusting the percentages of the source channels, you get the best results when the combined values of the source channels add up to 100%. If you go over 100%, you’ll overexpose an image and if you go under 100%, you will underexpose it.
Step 3: Applying the Channel Mixer command and may all most photographers may need to convert image files to monochrome, but if you want more power, it’s time to reach for power tools. More on that later …
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