There are a number of ways to generate a greyscale image of course, but for print production, they don’t always generate a true greyscale image. For example, if you use the Black and White Adjustment Layer, the image you have is still RGB. You can of course save a copy of that as a true greyscale, but that means if you need to tune the original, then you’ll need to create another copy.
Here’s a technique that you may want to employ, that gives you a true greyscale file, from one PSD original—”live” greyscale.
- Open your file, and if it isn’t already, convert it to a PSD. If you need to do this in bulk, then you could use the Image Processor script to do that for you.
- Convert your Background to a Smart Object.
- Change the Image Mode of the file to Greyscale—you’ll get an option dialog and choose Don’t Rasterize to preserve your Smart Object—the file will now behave and print as a true greyscale image, with one single channel.
- Save the file and keep the option to Maximize Compatibility.
- To edit/tune the greyscale values, double-click the Smart Object thumbnail in the Layers Panel.
- Once the Smart Object is open (you’ll know—it’ll be in colour) again, convert the background to a Smart Object, so that you can infinitely edit the image.
- From the Filter menu, choose the Camera Raw Filter. Assuming you’re ok with the colour values already—you can adjust them here if you want to—then choose the HSL/Greyscale tab on the right-hand side of the screen. Check the Convert to Greyscale box, and then tune as desired.
- Exit the dialog, save and exit the Smart Object and you’re back in the PSD, with a true greyscale image.
InDesign Tint Duotones
Greyscale images (TIFF, JPG or PNG) placed into InDesign can be tinted by applying a colour swatch to the image frame; InDesign treats the white values as transparent so you’re effectively “seeing through” the image to the colour underneath. The above technique doesn’t work for this kind of operation, but you could always go one step further—you’d have more control and a much finer result.
Now that you have your greyscale PSD, you can create a duotoned (or tritoned or quadtoned) version really easily.
The image being used in this post is “Lakeside of Mono Lake.jpg” by Michael Gäbler (licensed under Creative Commons) and can be found on Wikimedia: https://commons.wikimedia.org/wiki/File:Lakeside_of_Mono_Lake.jpg
Does this method make things easier for you? I’d love to hear your comments, and please share the post!
Note: This post didn’t get automatically published on time as planned—entirely my error, sorry—so if you’re a regular reader via a feed, there’s nothing wrong with your app/kit, it’s all down to me. I have deducted some awesome points from my running total.