Using Channel Mixer for Monochrome Infrared

by | Oct 28, 2020

Today’s Post by Joe Farace

First a confession: So far anyway, I have resisted buying into Adobe’s subscription service for Photoshop mainly because I cannot afford it. But I recognize that active pros need to have (and can afford) the latest tools. All of the Photoshop tips and tools that you see on this blog, not just today’s, were made using Photoshop CS6. For an interesting perspective on this choice, please read the last paragraph on this post that talks about my experience talking with a successful travel photographer and the software that he uses.

Photoshop’s Channel Mixer (Image > Adjustments > Channel Mixer) lets you produce grayscale images by letting you choose the percentage of contribution from each color channel. It modifies output using a mix of the existing image’s color channels allowing you to add or subtract data from a source channel to the output channel.

Step 1: The above image was captured with a Panasonic Lumix G5 that was converted to IR capture by LifePixel. The lens used was the Lumix G Vario 12-32mm f/3.5-5.6 at 12mm. Exposure was 1/640 sec at f/9 and ISO 400. The RAW file was then opened in Adobe Photoshop.

Step 2: The next step was selecting Channel Mixer. After opening its Control Panel, be sure to click the Monochrome check box at the bottom left and set Gray as the output channel in a pop-up menu. These settings produce a color image that only contains gray values.

Then move the sliders to control the amount of detail and contrast in the image that you’re converting to grayscale but be sure to watch how changes in each channel affects the final monochrome image, which is “live” as you work on it. Tip: When adjusting percentages of the source channels, you’ll 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 may be all many photographers need to convert their color image files—infrared or not— into monochrome photographs, but if you want more control, it’s time to reach for power tools. More to come on this subject…

Life Pixel does a great job with IR conversions and they have done most of the conversions for my Canon DSLRs and all of my Panasonic Lumix G-series cameras. This is not a paid or sponsored endorsement, just my experience.

My book, The Complete Guide to Digital Infrared Photography is out-of-print but used copies are available from Amazon for $14.99. with used copies starting at $5.73, as I write this. Creative Digital Monochrome Effects has a chapter on IR photography and is available from Amazon for $31.10 with used copies starting at aound two bucks. Mp Kindle versions of either book is currently available, sorry.